Guide to the Secure Configuration of Red Hat Enterprise Linux 7

with profile CIS Red Hat Enterprise Linux 7 Benchmark for Level 1 - Server
This profile defines a baseline that aligns to the "Level 1 - Server" configuration from the Center for Internet Security® Red Hat Enterprise Linux 7 Benchmark™, v3.1.1, released 05-21-2021. This profile includes Center for Internet Security® Red Hat Enterprise Linux 7 CIS Benchmarks™ content.
The SCAP Security Guide Project
https://www.open-scap.org/security-policies/scap-security-guide
This guide presents a catalog of security-relevant configuration settings for Red Hat Enterprise Linux 7. It is a rendering of content structured in the eXtensible Configuration Checklist Description Format (XCCDF) in order to support security automation. The SCAP content is is available in the scap-security-guide package which is developed at https://www.open-scap.org/security-policies/scap-security-guide.

Providing system administrators with such guidance informs them how to securely configure systems under their control in a variety of network roles. Policy makers and baseline creators can use this catalog of settings, with its associated references to higher-level security control catalogs, in order to assist them in security baseline creation. This guide is a catalog, not a checklist, and satisfaction of every item is not likely to be possible or sensible in many operational scenarios. However, the XCCDF format enables granular selection and adjustment of settings, and their association with OVAL and OCIL content provides an automated checking capability. Transformations of this document, and its associated automated checking content, are capable of providing baselines that meet a diverse set of policy objectives. Some example XCCDF Profiles, which are selections of items that form checklists and can be used as baselines, are available with this guide. They can be processed, in an automated fashion, with tools that support the Security Content Automation Protocol (SCAP). The DISA STIG, which provides required settings for US Department of Defense systems, is one example of a baseline created from this guidance.

This benchmark is a direct port of a SCAP Security Guide benchmark developed for Red Hat Enterprise Linux. It has been modified through an automated process to remove specific dependencies on Red Hat Enterprise Linux and to function with CentOS. The result is a generally useful SCAP Security Guide benchmark with the following caveats:

  • CentOS is not an exact copy of Red Hat Enterprise Linux. There may be configuration differences that produce false positives and/or false negatives. If this occurs please file a bug report.
  • CentOS has its own build system, compiler options, patchsets, and is a community supported, non-commercial operating system. CentOS does not inherit certifications or evaluations from Red Hat Enterprise Linux. As such, some configuration rules (such as those requiring FIPS 140-2 encryption) will continue to fail on CentOS.

Members of the CentOS community are invited to participate in OpenSCAP and SCAP Security Guide development. Bug reports and patches can be sent to GitHub: https://github.com/ComplianceAsCode/content. The mailing list is at https://fedorahosted.org/mailman/listinfo/scap-security-guide.

Do not attempt to implement any of the settings in this guide without first testing them in a non-operational environment. The creators of this guidance assume no responsibility whatsoever for its use by other parties, and makes no guarantees, expressed or implied, about its quality, reliability, or any other characteristic.

Profile Information

Profile TitleCIS Red Hat Enterprise Linux 7 Benchmark for Level 1 - Server
Profile IDxccdf_org.ssgproject.content_profile_cis_server_l1

CPE Platforms

  • cpe:/o:redhat:enterprise_linux:7::client
  • cpe:/o:redhat:enterprise_linux:7::computenode
  • cpe:/o:redhat:enterprise_linux:7::server
  • cpe:/o:redhat:enterprise_linux:7::workstation
  • cpe:/o:redhat:enterprise_linux:7
  • cpe:/o:centos:centos:7

Revision History

Current version: 0.1.66

  • draft (as of 2023-02-03)

Table of Contents

  1. System Settings
    1. Installing and Maintaining Software
    2. Account and Access Control
    3. GRUB2 bootloader configuration
    4. Configure Syslog
    5. Network Configuration and Firewalls
    6. File Permissions and Masks
    7. SELinux
  2. Services
    1. Avahi Server
    2. Cron and At Daemons
    3. DHCP
    4. DNS Server
    5. FTP Server
    6. Web Server
    7. IMAP and POP3 Server
    8. LDAP
    9. Mail Server Software
    10. NFS and RPC
    11. Network Time Protocol
    12. Obsolete Services
    13. Print Support
    14. Proxy Server
    15. Samba(SMB) Microsoft Windows File Sharing Server
    16. SNMP Server
    17. SSH Server
    18. X Window System

Checklist

Group   Guide to the Secure Configuration of Red Hat Enterprise Linux 7   Group contains 96 groups and 239 rules
Group   System Settings   Group contains 54 groups and 165 rules
[ref]   Contains rules that check correct system settings.
Group   Installing and Maintaining Software   Group contains 8 groups and 13 rules
[ref]   The following sections contain information on security-relevant choices during the initial operating system installation process and the setup of software updates.
Group   System and Software Integrity   Group contains 2 groups and 4 rules
[ref]   System and software integrity can be gained by installing antivirus, increasing system encryption strength with FIPS, verifying installed software, enabling SELinux, installing an Intrusion Prevention System, etc. However, installing or enabling integrity checking tools cannot prevent intrusions, but they can detect that an intrusion may have occurred. Requirements for integrity checking may be highly dependent on the environment in which the system will be used. Snapshot-based approaches such as AIDE may induce considerable overhead in the presence of frequent software updates.
Group   Software Integrity Checking   Group contains 1 group and 3 rules
[ref]   Both the AIDE (Advanced Intrusion Detection Environment) software and the RPM package management system provide mechanisms for verifying the integrity of installed software. AIDE uses snapshots of file metadata (such as hashes) and compares these to current system files in order to detect changes.

The RPM package management system can conduct integrity checks by comparing information in its metadata database with files installed on the system.
Group   Verify Integrity with AIDE   Group contains 3 rules
[ref]   AIDE conducts integrity checks by comparing information about files with previously-gathered information. Ideally, the AIDE database is created immediately after initial system configuration, and then again after any software update. AIDE is highly configurable, with further configuration information located in /usr/share/doc/aide-VERSION.

Rule   Install AIDE   [ref]

The aide package can be installed with the following command: 
$ sudo yum install aide
Rationale:
The AIDE package must be installed if it is to be available for integrity checking.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_aide_installed
Identifiers and References

References:  BP28(R51), 1, 11, 12, 13, 14, 15, 16, 2, 3, 5, 7, 8, 9, 5.10.1.3, APO01.06, BAI01.06, BAI02.01, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS03.05, DSS04.07, DSS05.02, DSS05.03, DSS05.05, DSS05.07, DSS06.02, DSS06.06, CCI-002696, CCI-002699, CCI-001744, 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.4, SR 3.1, SR 3.3, SR 3.4, SR 3.8, SR 4.1, SR 6.2, SR 7.6, 1034, 1288, 1341, 1417, A.11.2.4, A.12.1.2, A.12.2.1, A.12.4.1, A.12.5.1, A.12.6.2, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.14.2.7, A.15.2.1, A.8.2.3, CM-6(a), DE.CM-1, DE.CM-7, PR.DS-1, PR.DS-6, PR.DS-8, PR.IP-1, PR.IP-3, Req-11.5, SRG-OS-000445-GPOS-00199, 1.3.1, SV-251705r880854_rule


Complexity:low
Disruption:low
Strategy:enable
include install_aide

class install_aide {
  package { 'aide':
    ensure => 'installed',
  }
}

Complexity:low
Disruption:low
Strategy:enable

package --add=aide



[[packages]]
name = "aide"
version = "*"

Complexity:low
Disruption:low
Strategy:enable
- name: Ensure aide is installed
  package:
    name: aide
    state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.10.1.3
  - DISA-STIG-RHEL-07-020029
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-11.5
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_aide_installed

Complexity:low
Disruption:low
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if ! rpm -q --quiet "aide" ; then
    yum install -y "aide"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Build and Test AIDE Database   [ref]

Run the following command to generate a new database: 
$ sudo /usr/sbin/aide --init
By default, the database will be written to the file /var/lib/aide/aide.db.new.gz. Storing the database, the configuration file /etc/aide.conf, and the binary /usr/sbin/aide (or hashes of these files), in a secure location (such as on read-only media) provides additional assurance about their integrity. The newly-generated database can be installed as follows: 
$ sudo cp /var/lib/aide/aide.db.new.gz /var/lib/aide/aide.db.gz
To initiate a manual check, run the following command: 
$ sudo /usr/sbin/aide --check
If this check produces any unexpected output, investigate.
Rationale:
For AIDE to be effective, an initial database of "known-good" information about files must be captured and it should be able to be verified against the installed files.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_aide_build_database
Identifiers and References

References:  BP28(R51), 1, 11, 12, 13, 14, 15, 16, 2, 3, 5, 7, 8, 9, 5.10.1.3, APO01.06, BAI01.06, BAI02.01, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS03.05, DSS04.07, DSS05.02, DSS05.03, DSS05.05, DSS05.07, DSS06.02, DSS06.06, 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.4, SR 3.1, SR 3.3, SR 3.4, SR 3.8, SR 4.1, SR 6.2, SR 7.6, A.11.2.4, A.12.1.2, A.12.2.1, A.12.4.1, A.12.5.1, A.12.6.2, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.14.2.7, A.15.2.1, A.8.2.3, CM-6(a), DE.CM-1, DE.CM-7, PR.DS-1, PR.DS-6, PR.DS-8, PR.IP-1, PR.IP-3, Req-11.5, SRG-OS-000445-GPOS-00199, 1.3.1, SV-251705r880854_rule


Complexity:low
Disruption:low
Strategy:restrict
- name: Ensure AIDE is installed
  package:
    name: '{{ item }}'
    state: present
  with_items:
  - aide
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.10.1.3
  - DISA-STIG-RHEL-07-020029
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-11.5
  - aide_build_database
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Build and Test AIDE Database
  command: /usr/sbin/aide --init
  changed_when: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.10.1.3
  - DISA-STIG-RHEL-07-020029
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-11.5
  - aide_build_database
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Check whether the stock AIDE Database exists
  stat:
    path: /var/lib/aide/aide.db.new.gz
  register: aide_database_stat
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.10.1.3
  - DISA-STIG-RHEL-07-020029
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-11.5
  - aide_build_database
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Stage AIDE Database
  copy:
    src: /var/lib/aide/aide.db.new.gz
    dest: /var/lib/aide/aide.db.gz
    backup: true
    remote_src: true
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - (aide_database_stat.stat.exists is defined and aide_database_stat.stat.exists)
  tags:
  - CJIS-5.10.1.3
  - DISA-STIG-RHEL-07-020029
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-11.5
  - aide_build_database
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if ! rpm -q --quiet "aide" ; then
    yum install -y "aide"
fi

/usr/sbin/aide --init
/bin/cp -p /var/lib/aide/aide.db.new.gz /var/lib/aide/aide.db.gz

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Configure Periodic Execution of AIDE   [ref]

At a minimum, AIDE should be configured to run a weekly scan. To implement a daily execution of AIDE at 4:05am using cron, add the following line to /etc/crontab: 
05 4 * * * root /usr/sbin/aide --check
To implement a weekly execution of AIDE at 4:05am using cron, add the following line to /etc/crontab: 
05 4 * * 0 root /usr/sbin/aide --check
AIDE can be executed periodically through other means; this is merely one example. The usage of cron's special time codes, such as @daily and @weekly is acceptable.
Rationale:
By default, AIDE does not install itself for periodic execution. Periodically running AIDE is necessary to reveal unexpected changes in installed files.

Unauthorized changes to the baseline configuration could make the system vulnerable to various attacks or allow unauthorized access to the operating system. Changes to operating system configurations can have unintended side effects, some of which may be relevant to security.

Detecting such changes and providing an automated response can help avoid unintended, negative consequences that could ultimately affect the security state of the operating system. The operating system's Information Management Officer (IMO)/Information System Security Officer (ISSO) and System Administrators (SAs) must be notified via email and/or monitoring system trap when there is an unauthorized modification of a configuration item.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_aide_periodic_cron_checking
Identifiers and References

References:  BP28(R51), 1, 11, 12, 13, 14, 15, 16, 2, 3, 5, 7, 8, 9, 5.10.1.3, APO01.06, BAI01.06, BAI02.01, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS01.03, DSS03.05, DSS04.07, DSS05.02, DSS05.03, DSS05.05, DSS05.07, DSS06.02, DSS06.06, CCI-001744, CCI-002699, CCI-002702, 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.4, SR 3.1, SR 3.3, SR 3.4, SR 3.8, SR 4.1, SR 6.2, SR 7.6, A.11.2.4, A.12.1.2, A.12.2.1, A.12.4.1, A.12.5.1, A.12.6.2, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, A.14.2.7, A.15.2.1, A.8.2.3, SI-7, SI-7(1), CM-6(a), DE.CM-1, DE.CM-7, PR.DS-1, PR.DS-6, PR.DS-8, PR.IP-1, PR.IP-3, Req-11.5, SRG-OS-000363-GPOS-00150, SRG-OS-000446-GPOS-00200, SRG-OS-000447-GPOS-00201, 1.3.2, SV-204445r880848_rule


Complexity:low
Disruption:low
Strategy:restrict
- name: Ensure AIDE is installed
  package:
    name: '{{ item }}'
    state: present
  with_items:
  - aide
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.10.1.3
  - DISA-STIG-RHEL-07-020030
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - PCI-DSS-Req-11.5
  - aide_periodic_cron_checking
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set cron package name - RedHat
  set_fact:
    cron_pkg_name: cronie
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_os_family == "RedHat" or ansible_os_family == "Suse"
  tags:
  - CJIS-5.10.1.3
  - DISA-STIG-RHEL-07-020030
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - PCI-DSS-Req-11.5
  - aide_periodic_cron_checking
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set cron package name - Debian
  set_fact:
    cron_pkg_name: cron
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - ansible_os_family == "Debian"
  tags:
  - CJIS-5.10.1.3
  - DISA-STIG-RHEL-07-020030
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - PCI-DSS-Req-11.5
  - aide_periodic_cron_checking
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Install cron
  package:
    name: '{{ cron_pkg_name }}'
    state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.10.1.3
  - DISA-STIG-RHEL-07-020030
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - PCI-DSS-Req-11.5
  - aide_periodic_cron_checking
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Configure Periodic Execution of AIDE
  cron:
    name: run AIDE check
    minute: 5
    hour: 4
    weekday: 0
    user: root
    job: /usr/sbin/aide --check
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.10.1.3
  - DISA-STIG-RHEL-07-020030
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SI-7
  - NIST-800-53-SI-7(1)
  - PCI-DSS-Req-11.5
  - aide_periodic_cron_checking
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if ! rpm -q --quiet "aide" ; then
    yum install -y "aide"
fi

if ! grep -q "/usr/sbin/aide --check" /etc/crontab ; then
    echo "05 4 * * * root /usr/sbin/aide --check" >> /etc/crontab
else
    sed -i '\!^.* --check.*$!d' /etc/crontab
    echo "05 4 * * * root /usr/sbin/aide --check" >> /etc/crontab
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Disk Partitioning   Group contains 1 rule
[ref]   To ensure separation and protection of data, there are top-level system directories which should be placed on their own physical partition or logical volume. The installer's default partitioning scheme creates separate logical volumes for /, /boot, and swap.
  • If starting with any of the default layouts, check the box to \"Review and modify partitioning.\" This allows for the easy creation of additional logical volumes inside the volume group already created, though it may require making /'s logical volume smaller to create space. In general, using logical volumes is preferable to using partitions because they can be more easily adjusted later.
  • If creating a custom layout, create the partitions mentioned in the previous paragraph (which the installer will require anyway), as well as separate ones described in the following sections.
If a system has already been installed, and the default partitioning scheme was used, it is possible but nontrivial to modify it to create separate logical volumes for the directories listed above. The Logical Volume Manager (LVM) makes this possible. See the LVM HOWTO at http://tldp.org/HOWTO/LVM-HOWTO/ for more detailed information on LVM.

Rule   Ensure /tmp Located On Separate Partition   [ref]

The /tmp directory is a world-writable directory used for temporary file storage. Ensure it has its own partition or logical volume at installation time, or migrate it using LVM.
Rationale:
The /tmp partition is used as temporary storage by many programs. Placing /tmp in its own partition enables the setting of more restrictive mount options, which can help protect programs which use it.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_partition_for_tmp
Identifiers and References

References:  BP28(R12), 12, 15, 8, APO13.01, DSS05.02, CCI-000366, SR 3.1, SR 3.5, SR 3.8, SR 4.1, SR 4.3, SR 5.1, SR 5.2, SR 5.3, SR 7.1, SR 7.6, A.13.1.1, A.13.2.1, A.14.1.3, CM-6(a), SC-5(2), PR.PT-4, SRG-OS-000480-GPOS-00227, 1.1.2, SV-204496r603261_rule


Complexity:low
Disruption:high
Strategy:enable

part /tmp



[[customizations.filesystem]]
mountpoint = "/tmp"
size = 1073741824
Group   GNOME Desktop Environment   Group contains 1 group and 3 rules
[ref]   GNOME is a graphical desktop environment bundled with many Linux distributions that allow users to easily interact with the operating system graphically rather than textually. The GNOME Graphical Display Manager (GDM) provides login, logout, and user switching contexts as well as display server management.

GNOME is developed by the GNOME Project and is considered the default Red Hat Graphical environment.

For more information on GNOME and the GNOME Project, see https://www.gnome.org.
Group   Configure GNOME Login Screen   Group contains 2 rules

Rule   Disable the GNOME3 Login User List   [ref]

In the default graphical environment, users logging directly into the system are greeted with a login screen that displays all known users. This functionality should be disabled by setting disable-user-list to true.

To disable, add or edit disable-user-list to /etc/dconf/db/gdm.d/00-security-settings. For example: 
[org/gnome/login-screen]
disable-user-list=true
Once the setting has been added, add a lock to /etc/dconf/db/gdm.d/locks/00-security-settings-lock to prevent user modification. For example: 
/org/gnome/login-screen/disable-user-list
After the settings have been set, run dconf update.
Rationale:
Leaving the user list enabled is a security risk since it allows anyone with physical access to the system to quickly enumerate known user accounts without logging in.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_dconf_gnome_disable_user_list
Identifiers and References

References:  CM-6(a), AC-23, SRG-OS-000480-GPOS-00227, 1.8.3


Complexity:low
Disruption:medium
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AC-23
  - NIST-800-53-CM-6(a)
  - dconf_gnome_disable_user_list
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy

- name: Disable the GNOME3 Login User List
  ini_file:
    dest: /etc/dconf/db/gdm.d/00-security-settings
    section: org/gnome/login-screen
    option: disable-user-list
    value: 'true'
    no_extra_spaces: true
    create: true
  when:
  - '"gdm" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-53-AC-23
  - NIST-800-53-CM-6(a)
  - dconf_gnome_disable_user_list
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy

- name: Prevent user modification of GNOME3 disablement of Login User List
  lineinfile:
    path: /etc/dconf/db/gdm.d/locks/00-security-settings-lock
    regexp: ^/org/gnome/login-screen/disable-user-list$
    line: /org/gnome/login-screen/disable-user-list
    create: true
  when:
  - '"gdm" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-53-AC-23
  - NIST-800-53-CM-6(a)
  - dconf_gnome_disable_user_list
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy

- name: Dconf Update
  command: dconf update
  when:
  - '"gdm" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-53-AC-23
  - NIST-800-53-CM-6(a)
  - dconf_gnome_disable_user_list
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy


# Remediation is applicable only in certain platforms
if rpm --quiet -q gdm && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

# Check for setting in any of the DConf db directories
# If files contain ibus or distro, ignore them.
# The assignment assumes that individual filenames don't contain :
readarray -t SETTINGSFILES < <(grep -r "\\[org/gnome/login-screen\\]" "/etc/dconf/db/" \
                                | grep -v 'distro\|ibus\|gdm.d' | cut -d":" -f1)
DCONFFILE="/etc/dconf/db/gdm.d/00-security-settings"
DBDIR="/etc/dconf/db/gdm.d"

mkdir -p "${DBDIR}"

# Comment out the configurations in databases different from the target one
if [ "${#SETTINGSFILES[@]}" -ne 0 ]
then
    if grep -q "^\\s*disable-user-list\\s*=" "${SETTINGSFILES[@]}"
    then
        
        sed -Ei "s/(^\s*)disable-user-list(\s*=)/#\1disable-user-list\2/g" "${SETTINGSFILES[@]}"
    fi
fi


[ ! -z "${DCONFFILE}" ] && echo "" >> "${DCONFFILE}"
if ! grep -q "\\[org/gnome/login-screen\\]" "${DCONFFILE}"
then
    printf '%s\n' "[org/gnome/login-screen]" >> ${DCONFFILE}
fi

escaped_value="$(sed -e 's/\\/\\\\/g' <<< "true")"
if grep -q "^\\s*disable-user-list\\s*=" "${DCONFFILE}"
then
        sed -i "s/\\s*disable-user-list\\s*=\\s*.*/disable-user-list=${escaped_value}/g" "${DCONFFILE}"
    else
        sed -i "\\|\\[org/gnome/login-screen\\]|a\\disable-user-list=${escaped_value}" "${DCONFFILE}"
fi

dconf update
# Check for setting in any of the DConf db directories
LOCKFILES=$(grep -r "^/org/gnome/login-screen/disable-user-list$" "/etc/dconf/db/" \
            | grep -v 'distro\|ibus\|gdm.d' | grep ":" | cut -d":" -f1)
LOCKSFOLDER="/etc/dconf/db/gdm.d/locks"

mkdir -p "${LOCKSFOLDER}"

# Comment out the configurations in databases different from the target one
if [[ ! -z "${LOCKFILES}" ]]
then
    sed -i -E "s|^/org/gnome/login-screen/disable-user-list$|#&|" "${LOCKFILES[@]}"
fi

if ! grep -qr "^/org/gnome/login-screen/disable-user-list$" /etc/dconf/db/gdm.d/
then
    echo "/org/gnome/login-screen/disable-user-list" >> "/etc/dconf/db/gdm.d/locks/00-security-settings-lock"
fi

dconf update

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Disable XDMCP in GDM   [ref]

XDMCP is an unencrypted protocol, and therefore, presents a security risk, see e.g. XDMCP Gnome docs. To disable XDMCP support in Gnome, set Enable to false under the [xdmcp] configuration section in /etc/gdm/custom.conf. For example: 
[xdmcp]
Enable=false
Rationale:
XDMCP provides unencrypted remote access through the Gnome Display Manager (GDM) which does not provide for the confidentiality and integrity of user passwords or the remote session. If a privileged user were to login using XDMCP, the privileged user password could be compromised due to typed XEvents and keystrokes will traversing over the network in clear text.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_gnome_gdm_disable_xdmcp
Identifiers and References

References:  1.8.4


Complexity:low
Disruption:medium
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - gnome_gdm_disable_xdmcp
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed
  - unknown_strategy

- name: Disable XDMCP in GDM
  ini_file:
    path: /etc/gdm/custom.conf
    section: xdmcp
    option: Enable
    value: 'false'
    create: true
    mode: 420
  when: '"gdm" in ansible_facts.packages'
  tags:
  - gnome_gdm_disable_xdmcp
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed
  - unknown_strategy


# Remediation is applicable only in certain platforms
if rpm --quiet -q gdm; then

# Try find '[xdmcp]' and 'Enable' in '/etc/gdm/custom.conf', if it exists, set
# to 'false', if it isn't here, add it, if '[xdmcp]' doesn't exist, add it there
if grep -qzosP '[[:space:]]*\[xdmcp]([^\n\[]*\n+)+?[[:space:]]*Enable' '/etc/gdm/custom.conf'; then
    
    sed -i "s/Enable[^(\n)]*/Enable=false/" '/etc/gdm/custom.conf'
elif grep -qs '[[:space:]]*\[xdmcp]' '/etc/gdm/custom.conf'; then
    sed -i "/[[:space:]]*\[xdmcp]/a Enable=false" '/etc/gdm/custom.conf'
else
    if test -d "/etc/gdm"; then
        printf '%s\n' '[xdmcp]' "Enable=false" >> '/etc/gdm/custom.conf'
    else
        echo "Config file directory '/etc/gdm' doesnt exist, not remediating, assuming non-applicability." >&2
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Make sure that the dconf databases are up-to-date with regards to respective keyfiles   [ref]

By default, DConf uses a binary database as a data backend. The system-level database is compiled from keyfiles in the /etc/dconf/db/ directory by the 
dconf update
command. More specifically, content present in the following directories: 
/etc/dconf/db/gdm.d
/etc/dconf/db/local.d
Rationale:
Unlike text-based keyfiles, the binary database is impossible to check by OVAL. Therefore, in order to evaluate dconf configuration, both have to be true at the same time - configuration files have to be compliant, and the database needs to be more recent than those keyfiles, which gives confidence that it reflects them.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_dconf_db_up_to_date
Identifiers and References

References:  164.308(a)(1)(ii)(B), 164.308(a)(5)(ii)(A), Req-6.2, SRG-OS-000480-GPOS-00227, 1.7.2


# Remediation is applicable only in certain platforms
if rpm --quiet -q gdm && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

dconf update

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Sudo   Group contains 3 rules
[ref]   Sudo, which stands for "su 'do'", provides the ability to delegate authority to certain users, groups of users, or system administrators. When configured for system users and/or groups, Sudo can allow a user or group to execute privileged commands that normally only root is allowed to execute.

For more information on Sudo and addition Sudo configuration options, see https://www.sudo.ws.

Rule   Install sudo Package   [ref]

The sudo package can be installed with the following command: 
$ sudo yum install sudo
Rationale:
sudo is a program designed to allow a system administrator to give limited root privileges to users and log root activity. The basic philosophy is to give as few privileges as possible but still allow system users to get their work done.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_sudo_installed
Identifiers and References

References:  BP28(R19), 1382, 1384, 1386, CM-6(a), FMT_MOF_EXT.1, Req-10.2.1.5, SRG-OS-000324-GPOS-00125, 5.2.1


Complexity:low
Disruption:low
Strategy:enable
include install_sudo

class install_sudo {
  package { 'sudo':
    ensure => 'installed',
  }
}

Complexity:low
Disruption:low
Strategy:enable

package --add=sudo



[[packages]]
name = "sudo"
version = "*"

Complexity:low
Disruption:low
Strategy:enable
- name: Ensure sudo is installed
  package:
    name: sudo
    state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.2.1.5
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_sudo_installed

Complexity:low
Disruption:low
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if ! rpm -q --quiet "sudo" ; then
    yum install -y "sudo"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure Only Users Logged In To Real tty Can Execute Sudo - sudo use_pty   [ref]

The sudo use_pty tag, when specified, will only execute sudo commands from users logged in to a real tty. This should be enabled by making sure that the use_pty tag exists in /etc/sudoers configuration file or any sudo configuration snippets in /etc/sudoers.d/.
Rationale:
Requiring that sudo commands be run in a pseudo-terminal can prevent an attacker from retaining access to the user's terminal after the main program has finished executing.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sudo_add_use_pty
Identifiers and References

References:  BP28(R58), Req-10.2.1.5, 5.2.2


Complexity:low
Disruption:low
Strategy:restrict
- name: Ensure use_pty is enabled in /etc/sudoers
  lineinfile:
    path: /etc/sudoers
    regexp: ^[\s]*Defaults.*\buse_pty\b.*$
    line: Defaults use_pty
    validate: /usr/sbin/visudo -cf %s
  tags:
  - PCI-DSS-Req-10.2.1.5
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_add_use_pty

Complexity:low
Disruption:low
Strategy:restrict

if /usr/sbin/visudo -qcf /etc/sudoers; then
    cp /etc/sudoers /etc/sudoers.bak
    if ! grep -P '^[\s]*Defaults[\s]*\buse_pty\b.*$' /etc/sudoers; then
        # sudoers file doesn't define Option use_pty
        echo "Defaults use_pty" >> /etc/sudoers
    fi
    
    # Check validity of sudoers and cleanup bak
    if /usr/sbin/visudo -qcf /etc/sudoers; then
        rm -f /etc/sudoers.bak
    else
        echo "Fail to validate remediated /etc/sudoers, reverting to original file."
        mv /etc/sudoers.bak /etc/sudoers
        false
    fi
else
    echo "Skipping remediation, /etc/sudoers failed to validate"
    false
fi

Rule   Ensure Sudo Logfile Exists - sudo logfile   [ref]

A custom log sudo file can be configured with the 'logfile' tag. This rule configures a sudo custom logfile at the default location suggested by CIS, which uses /var/log/sudo.log.
Rationale:
A sudo log file simplifies auditing of sudo commands.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_sudo_custom_logfile
Identifiers and References

References:  Req-10.2.1.5, 5.2.3


Complexity:low
Disruption:low
Strategy:restrict
- name: XCCDF Value var_sudo_logfile # promote to variable
  set_fact:
    var_sudo_logfile: !!str /var/log/sudo.log
  tags:
    - always

- name: Ensure logfile is enabled with the appropriate value in /etc/sudoers
  lineinfile:
    path: /etc/sudoers
    regexp: ^[\s]*Defaults\s(.*)\blogfile=[-]?.+\b(.*)$
    line: Defaults \1logfile={{ var_sudo_logfile }}\2
    validate: /usr/sbin/visudo -cf %s
    backrefs: true
  register: edit_sudoers_logfile_option
  tags:
  - PCI-DSS-Req-10.2.1.5
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_custom_logfile

- name: Enable logfile option with appropriate value in /etc/sudoers
  lineinfile:
    path: /etc/sudoers
    line: Defaults logfile={{ var_sudo_logfile }}
    validate: /usr/sbin/visudo -cf %s
  when: edit_sudoers_logfile_option is defined and not edit_sudoers_logfile_option.changed
  tags:
  - PCI-DSS-Req-10.2.1.5
  - low_complexity
  - low_disruption
  - low_severity
  - no_reboot_needed
  - restrict_strategy
  - sudo_custom_logfile

Complexity:low
Disruption:low
Strategy:restrict


var_sudo_logfile='/var/log/sudo.log'


if /usr/sbin/visudo -qcf /etc/sudoers; then
    cp /etc/sudoers /etc/sudoers.bak
    if ! grep -P '^[\s]*Defaults[\s]*\blogfile=("(?:\\"|\\\\|[^"\\\n])*"\B|[^"](?:(?:\\,|\\"|\\ |\\\\|[^", \\\n])*)\b)\b.*$' /etc/sudoers; then
        # sudoers file doesn't define Option logfile
        echo "Defaults logfile=${var_sudo_logfile}" >> /etc/sudoers
    else
        # sudoers file defines Option logfile, remediate if appropriate value is not set
        if ! grep -P "^[\s]*Defaults.*\blogfile=${var_sudo_logfile}\b.*$" /etc/sudoers; then
            
            escaped_variable=${var_sudo_logfile//$'/'/$'\/'}
            sed -Ei "s/(^[\s]*Defaults.*\blogfile=)[-]?.+(\b.*$)/\1$escaped_variable\2/" /etc/sudoers
        fi
    fi
    
    # Check validity of sudoers and cleanup bak
    if /usr/sbin/visudo -qcf /etc/sudoers; then
        rm -f /etc/sudoers.bak
    else
        echo "Fail to validate remediated /etc/sudoers, reverting to original file."
        mv /etc/sudoers.bak /etc/sudoers
        false
    fi
else
    echo "Skipping remediation, /etc/sudoers failed to validate"
    false
fi
Group   Updating Software   Group contains 2 rules
[ref]   The yum command line tool is used to install and update software packages. The system also provides a graphical software update tool in the System menu, in the Administration submenu, called Software Update.

Red Hat Enterprise Linux 7 systems contain an installed software catalog called the RPM database, which records metadata of installed packages. Consistently using yum or the graphical Software Update for all software installation allows for insight into the current inventory of installed software on the system.

Rule   Ensure gpgcheck Enabled In Main yum Configuration   [ref]

The gpgcheck option controls whether RPM packages' signatures are always checked prior to installation. To configure yum to check package signatures before installing them, ensure the following line appears in /etc/yum.conf in the [main] section: 
gpgcheck=1
Rationale:
Changes to any software components can have significant effects on the overall security of the operating system. This requirement ensures the software has not been tampered with and that it has been provided by a trusted vendor.
Accordingly, patches, service packs, device drivers, or operating system components must be signed with a certificate recognized and approved by the organization.
Verifying the authenticity of the software prior to installation validates the integrity of the patch or upgrade received from a vendor. This ensures the software has not been tampered with and that it has been provided by a trusted vendor. Self-signed certificates are disallowed by this requirement. Certificates used to verify the software must be from an approved Certificate Authority (CA).
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_ensure_gpgcheck_globally_activated
Identifiers and References

References:  BP28(R15), 11, 2, 3, 9, 5.10.4.1, APO01.06, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS06.02, 3.4.8, CCI-001749, 164.308(a)(1)(ii)(D), 164.312(b), 164.312(c)(1), 164.312(c)(2), 164.312(e)(2)(i), 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.4, SR 3.1, SR 3.3, SR 3.4, SR 3.8, SR 7.6, A.11.2.4, A.12.1.2, A.12.2.1, A.12.5.1, A.12.6.2, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, CM-5(3), SI-7, SC-12, SC-12(3), CM-6(a), SA-12, SA-12(10), CM-11(a), CM-11(b), PR.DS-6, PR.DS-8, PR.IP-1, FPT_TUD_EXT.1, FPT_TUD_EXT.2, Req-6.2, SRG-OS-000366-GPOS-00153, SRG-OS-000366-VMM-001430, SRG-OS-000370-VMM-001460, SRG-OS-000404-VMM-001650, 1.2.3, SV-204447r877463_rule


Complexity:low
Disruption:medium
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-020050
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-11(a)
  - NIST-800-53-CM-11(b)
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SA-12
  - NIST-800-53-SA-12(10)
  - NIST-800-53-SC-12
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SI-7
  - PCI-DSS-Req-6.2
  - configure_strategy
  - ensure_gpgcheck_globally_activated
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed

- name: Ensure GPG check is globally activated
  ini_file:
    dest: /etc/yum.conf
    section: main
    option: gpgcheck
    value: 1
    no_extra_spaces: true
    create: false
  when: '"yum" in ansible_facts.packages'
  tags:
  - CJIS-5.10.4.1
  - DISA-STIG-RHEL-07-020050
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-11(a)
  - NIST-800-53-CM-11(b)
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SA-12
  - NIST-800-53-SA-12(10)
  - NIST-800-53-SC-12
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SI-7
  - PCI-DSS-Req-6.2
  - configure_strategy
  - ensure_gpgcheck_globally_activated
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed


# Remediation is applicable only in certain platforms
if rpm --quiet -q yum; then

# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/yum.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^gpgcheck")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "1"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^gpgcheck\\>" "/etc/yum.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    "${sed_command[@]}" "s/^gpgcheck\\>.*/$escaped_formatted_output/gi" "/etc/yum.conf"
else
    # \n is precaution for case where file ends without trailing newline
    cce=""
    printf '\n# Per %s: Set %s in %s\n' "$cce" "$formatted_output" "/etc/yum.conf" >> "/etc/yum.conf"
    printf '%s\n' "$formatted_output" >> "/etc/yum.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure gpgcheck Enabled for All yum Package Repositories   [ref]

To ensure signature checking is not disabled for any repos, remove any lines from files in /etc/yum.repos.d of the form: 
gpgcheck=0
Rationale:
Verifying the authenticity of the software prior to installation validates the integrity of the patch or upgrade received from a vendor. This ensures the software has not been tampered with and that it has been provided by a trusted vendor. Self-signed certificates are disallowed by this requirement. Certificates used to verify the software must be from an approved Certificate Authority (CA)."
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_ensure_gpgcheck_never_disabled
Identifiers and References

References:  BP28(R15), 11, 2, 3, 9, 5.10.4.1, APO01.06, BAI03.05, BAI06.01, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS06.02, 3.4.8, CCI-001749, 164.308(a)(1)(ii)(D), 164.312(b), 164.312(c)(1), 164.312(c)(2), 164.312(e)(2)(i), 4.3.4.3.2, 4.3.4.3.3, 4.3.4.4.4, SR 3.1, SR 3.3, SR 3.4, SR 3.8, SR 7.6, A.11.2.4, A.12.1.2, A.12.2.1, A.12.5.1, A.12.6.2, A.14.1.2, A.14.1.3, A.14.2.2, A.14.2.3, A.14.2.4, CM-5(3), SI-7, SC-12, SC-12(3), CM-6(a), SA-12, SA-12(10), CM-11(a), CM-11(b), PR.DS-6, PR.DS-8, PR.IP-1, FPT_TUD_EXT.1, FPT_TUD_EXT.2, Req-6.2, SRG-OS-000366-GPOS-00153, SRG-OS-000366-VMM-001430, SRG-OS-000370-VMM-001460, SRG-OS-000404-VMM-001650, 1.2.3


Complexity:low
Disruption:medium
Strategy:enable
- name: Grep for yum repo section names
  shell: |
    set -o pipefail
    grep -HEr '^\[.+\]' -r /etc/yum.repos.d/
  register: repo_grep_results
  ignore_errors: true
  changed_when: false
  tags:
  - CJIS-5.10.4.1
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-11(a)
  - NIST-800-53-CM-11(b)
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SA-12
  - NIST-800-53-SA-12(10)
  - NIST-800-53-SC-12
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SI-7
  - PCI-DSS-Req-6.2
  - enable_strategy
  - ensure_gpgcheck_never_disabled
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed

- name: Set gpgcheck=1 for each yum repo
  ini_file:
    path: '{{ item[0] }}'
    section: '{{ item[1] }}'
    option: gpgcheck
    value: '1'
    no_extra_spaces: true
  loop: '{{ repo_grep_results.stdout | regex_findall( ''(.+\.repo):\[(.+)\]\n?'' )
    }}'
  tags:
  - CJIS-5.10.4.1
  - NIST-800-171-3.4.8
  - NIST-800-53-CM-11(a)
  - NIST-800-53-CM-11(b)
  - NIST-800-53-CM-5(3)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SA-12
  - NIST-800-53-SA-12(10)
  - NIST-800-53-SC-12
  - NIST-800-53-SC-12(3)
  - NIST-800-53-SI-7
  - PCI-DSS-Req-6.2
  - enable_strategy
  - ensure_gpgcheck_never_disabled
  - high_severity
  - low_complexity
  - medium_disruption
  - no_reboot_needed



sed -i 's/gpgcheck\s*=.*/gpgcheck=1/g' /etc/yum.repos.d/*
Group   Account and Access Control   Group contains 16 groups and 45 rules
[ref]   In traditional Unix security, if an attacker gains shell access to a certain login account, they can perform any action or access any file to which that account has access. Therefore, making it more difficult for unauthorized people to gain shell access to accounts, particularly to privileged accounts, is a necessary part of securing a system. This section introduces mechanisms for restricting access to accounts under Red Hat Enterprise Linux 7.
Group   Warning Banners for System Accesses   Group contains 1 group and 14 rules
[ref]   Each system should expose as little information about itself as possible.

System banners, which are typically displayed just before a login prompt, give out information about the service or the host's operating system. This might include the distribution name and the system kernel version, and the particular version of a network service. This information can assist intruders in gaining access to the system as it can reveal whether the system is running vulnerable software. Most network services can be configured to limit what information is displayed.

Many organizations implement security policies that require a system banner provide notice of the system's ownership, provide warning to unauthorized users, and remind authorized users of their consent to monitoring.
Group   Implement a GUI Warning Banner   Group contains 2 rules

Rule   Enable GNOME3 Login Warning Banner   [ref]

In the default graphical environment, displaying a login warning banner in the GNOME Display Manager's login screen can be enabled on the login screen by setting banner-message-enable to true.

To enable, add or edit banner-message-enable to /etc/dconf/db/gdm.d/00-security-settings. For example: 
[org/gnome/login-screen]
banner-message-enable=true
Once the setting has been added, add a lock to /etc/dconf/db/gdm.d/locks/00-security-settings-lock to prevent user modification. For example: 
/org/gnome/login-screen/banner-message-enable
After the settings have been set, run dconf update. The banner text must also be set.
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.

For U.S. Government systems, system use notifications are required only for access via login interfaces with human users and are not required when such human interfaces do not exist.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_dconf_gnome_banner_enabled
Identifiers and References

References:  1, 12, 15, 16, DSS05.04, DSS05.10, DSS06.10, 3.1.9, CCI-000048, CCI-000050, CCI-001384, CCI-001385, CCI-001386, CCI-001387, CCI-001388, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, AC-8(a), AC-8(b), AC-8(c), PR.AC-7, FMT_MOF_EXT.1, SRG-OS-000023-GPOS-00006, SRG-OS-000228-GPOS-00088, 1.8.2, SV-204393r603261_rule


Complexity:low
Disruption:medium
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - DISA-STIG-RHEL-07-010030
  - NIST-800-171-3.1.9
  - NIST-800-53-AC-8(a)
  - NIST-800-53-AC-8(b)
  - NIST-800-53-AC-8(c)
  - dconf_gnome_banner_enabled
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy

- name: Enable GNOME3 Login Warning Banner
  ini_file:
    dest: /etc/dconf/db/gdm.d/00-security-settings
    section: org/gnome/login-screen
    option: banner-message-enable
    value: 'true'
    create: true
    no_extra_spaces: true
  when: '"gdm" in ansible_facts.packages'
  tags:
  - DISA-STIG-RHEL-07-010030
  - NIST-800-171-3.1.9
  - NIST-800-53-AC-8(a)
  - NIST-800-53-AC-8(b)
  - NIST-800-53-AC-8(c)
  - dconf_gnome_banner_enabled
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy

- name: Prevent user modification of GNOME banner-message-enabled
  lineinfile:
    path: /etc/dconf/db/gdm.d/locks/00-security-settings-lock
    regexp: ^/org/gnome/login-screen/banner-message-enable$
    line: /org/gnome/login-screen/banner-message-enable
    create: true
  when: '"gdm" in ansible_facts.packages'
  tags:
  - DISA-STIG-RHEL-07-010030
  - NIST-800-171-3.1.9
  - NIST-800-53-AC-8(a)
  - NIST-800-53-AC-8(b)
  - NIST-800-53-AC-8(c)
  - dconf_gnome_banner_enabled
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy

- name: Dconf Update
  command: dconf update
  when: '"gdm" in ansible_facts.packages'
  tags:
  - DISA-STIG-RHEL-07-010030
  - NIST-800-171-3.1.9
  - NIST-800-53-AC-8(a)
  - NIST-800-53-AC-8(b)
  - NIST-800-53-AC-8(c)
  - dconf_gnome_banner_enabled
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy


# Remediation is applicable only in certain platforms
if rpm --quiet -q gdm; then

# Check for setting in any of the DConf db directories
# If files contain ibus or distro, ignore them.
# The assignment assumes that individual filenames don't contain :
readarray -t SETTINGSFILES < <(grep -r "\\[org/gnome/login-screen\\]" "/etc/dconf/db/" \
                                | grep -v 'distro\|ibus\|gdm.d' | cut -d":" -f1)
DCONFFILE="/etc/dconf/db/gdm.d/00-security-settings"
DBDIR="/etc/dconf/db/gdm.d"

mkdir -p "${DBDIR}"

# Comment out the configurations in databases different from the target one
if [ "${#SETTINGSFILES[@]}" -ne 0 ]
then
    if grep -q "^\\s*banner-message-enable\\s*=" "${SETTINGSFILES[@]}"
    then
        
        sed -Ei "s/(^\s*)banner-message-enable(\s*=)/#\1banner-message-enable\2/g" "${SETTINGSFILES[@]}"
    fi
fi


[ ! -z "${DCONFFILE}" ] && echo "" >> "${DCONFFILE}"
if ! grep -q "\\[org/gnome/login-screen\\]" "${DCONFFILE}"
then
    printf '%s\n' "[org/gnome/login-screen]" >> ${DCONFFILE}
fi

escaped_value="$(sed -e 's/\\/\\\\/g' <<< "true")"
if grep -q "^\\s*banner-message-enable\\s*=" "${DCONFFILE}"
then
        sed -i "s/\\s*banner-message-enable\\s*=\\s*.*/banner-message-enable=${escaped_value}/g" "${DCONFFILE}"
    else
        sed -i "\\|\\[org/gnome/login-screen\\]|a\\banner-message-enable=${escaped_value}" "${DCONFFILE}"
fi

dconf update
# Check for setting in any of the DConf db directories
LOCKFILES=$(grep -r "^/org/gnome/login-screen/banner-message-enable$" "/etc/dconf/db/" \
            | grep -v 'distro\|ibus\|gdm.d' | grep ":" | cut -d":" -f1)
LOCKSFOLDER="/etc/dconf/db/gdm.d/locks"

mkdir -p "${LOCKSFOLDER}"

# Comment out the configurations in databases different from the target one
if [[ ! -z "${LOCKFILES}" ]]
then
    sed -i -E "s|^/org/gnome/login-screen/banner-message-enable$|#&|" "${LOCKFILES[@]}"
fi

if ! grep -qr "^/org/gnome/login-screen/banner-message-enable$" /etc/dconf/db/gdm.d/
then
    echo "/org/gnome/login-screen/banner-message-enable" >> "/etc/dconf/db/gdm.d/locks/00-security-settings-lock"
fi

dconf update

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Modify the System Login Banner   [ref]

To configure the system login banner edit /etc/issue. Replace the default text with a message compliant with the local site policy or a legal disclaimer. The DoD required text is either:

You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions:
-The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations.
-At any time, the USG may inspect and seize data stored on this IS.
-Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose.
-This IS includes security measures (e.g., authentication and access controls) to protect USG interests -- not for your personal benefit or privacy.
-Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details.

OR:

I've read & consent to terms in IS user agreem't.
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.

System use notifications are required only for access via login interfaces with human users and are not required when such human interfaces do not exist.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_banner_etc_issue
Identifiers and References

References:  1, 12, 15, 16, DSS05.04, DSS05.10, DSS06.10, 3.1.9, CCI-000048, CCI-000050, CCI-001384, CCI-001385, CCI-001386, CCI-001387, CCI-001388, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, AC-8(a), AC-8(c), PR.AC-7, FMT_MOF_EXT.1, SRG-OS-000023-GPOS-00006, SRG-OS-000228-GPOS-00088, SRG-OS-000023-VMM-000060, SRG-OS-000024-VMM-000070, 1.7.2, SV-204395r603261_rule


Complexity:low
Disruption:medium
- name: XCCDF Value login_banner_text # promote to variable
  set_fact:
    login_banner_text: !!str ^(Authorized[\s\n]+uses[\s\n]+only\.[\s\n]+All[\s\n]+activity[\s\n]+may[\s\n]+be[\s\n]+monitored[\s\n]+and[\s\n]+reported\.|^(?!.*(\\|fedora|rhel|sle|ubuntu)).*)$
  tags:
    - always

- name: Modify the System Login Banner - ensure correct banner
  copy:
    dest: /etc/issue
    content: '{{ login_banner_text | regex_replace("^\^(.*)\$$", "\1") | regex_replace("^\((.*\.)\|.*\)$",
      "\1") | regex_replace("\[\\s\\n\]\+"," ") | regex_replace("\(\?:\[\\n\]\+\|\(\?:\\\\n\)\+\)",
      "\n") | regex_replace("\\", "") | wordwrap() }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - DISA-STIG-RHEL-07-010050
  - NIST-800-171-3.1.9
  - NIST-800-53-AC-8(a)
  - NIST-800-53-AC-8(c)
  - banner_etc_issue
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

login_banner_text='^(Authorized[\s\n]+uses[\s\n]+only\.[\s\n]+All[\s\n]+activity[\s\n]+may[\s\n]+be[\s\n]+monitored[\s\n]+and[\s\n]+reported\.|^(?!.*(\\|fedora|rhel|sle|ubuntu)).*)$'


# Multiple regexes transform the banner regex into a usable banner
# 0 - Remove anchors around the banner text
login_banner_text=$(echo "$login_banner_text" | sed 's/^\^\(.*\)\$$/\1/g')
# 1 - Keep only the first banners if there are multiple
#    (dod_banners contains the long and short banner)
login_banner_text=$(echo "$login_banner_text" | sed 's/^(\(.*\.\)|.*)$/\1/g')
# 2 - Add spaces ' '. (Transforms regex for "space or newline" into a " ")
login_banner_text=$(echo "$login_banner_text" | sed 's/\[\\s\\n\]+/ /g')
# 3 - Adds newlines. (Transforms "(?:\[\\n\]+|(?:\\n)+)" into "\n")
login_banner_text=$(echo "$login_banner_text" | sed 's/(?:\[\\n\]+|(?:\\\\n)+)/\n/g')
# 4 - Remove any leftover backslash. (From any parethesis in the banner, for example).
login_banner_text=$(echo "$login_banner_text" | sed 's/\\//g')
formatted=$(echo "$login_banner_text" | fold -sw 80)

cat <<EOF >/etc/issue
$formatted
EOF

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Modify the System Login Banner for Remote Connections   [ref]

To configure the system login banner edit /etc/issue.net. Replace the default text with a message compliant with the local site policy or a legal disclaimer. The DoD required text is either:

You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions:
-The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations.
-At any time, the USG may inspect and seize data stored on this IS.
-Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose.
-This IS includes security measures (e.g., authentication and access controls) to protect USG interests -- not for your personal benefit or privacy.
-Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details.

OR:

I've read & consent to terms in IS user agreem't.
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.

System use notifications are required only for access via login interfaces with human users and are not required when such human interfaces do not exist.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_banner_etc_issue_net
Identifiers and References

References:  CCI-000048, CCI-001384, CCI-001385, CCI-001386, CCI-001387, CCI-001388, SRG-OS-000023-GPOS-00006, SRG-OS-000228-GPOS-00088, 1.7.3


Complexity:low
Disruption:medium
- name: XCCDF Value login_banner_text # promote to variable
  set_fact:
    login_banner_text: !!str ^(Authorized[\s\n]+uses[\s\n]+only\.[\s\n]+All[\s\n]+activity[\s\n]+may[\s\n]+be[\s\n]+monitored[\s\n]+and[\s\n]+reported\.|^(?!.*(\\|fedora|rhel|sle|ubuntu)).*)$
  tags:
    - always

- name: Modify the System Login Banner for Remote Connections - ensure correct banner
  copy:
    dest: /etc/issue.net
    content: '{{ login_banner_text | regex_replace("^\^(.*)\$$", "\1") | regex_replace("^\((.*\.)\|.*\)$",
      "\1") | regex_replace("\[\\s\\n\]\+"," ") | regex_replace("\(\?:\[\\n\]\+\|\(\?:\\\\n\)\+\)",
      "\n") | regex_replace("\\", "") | wordwrap() }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - banner_etc_issue_net
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

login_banner_text='^(Authorized[\s\n]+uses[\s\n]+only\.[\s\n]+All[\s\n]+activity[\s\n]+may[\s\n]+be[\s\n]+monitored[\s\n]+and[\s\n]+reported\.|^(?!.*(\\|fedora|rhel|sle|ubuntu)).*)$'


# Multiple regexes transform the banner regex into a usable banner
# 0 - Remove anchors around the banner text
login_banner_text=$(echo "$login_banner_text" | sed 's/^\^\(.*\)\$$/\1/g')
# 1 - Keep only the first banners if there are multiple
#    (dod_banners contains the long and short banner)
login_banner_text=$(echo "$login_banner_text" | sed 's/^(\(.*\.\)|.*)$/\1/g')
# 2 - Add spaces ' '. (Transforms regex for "space or newline" into a " ")
login_banner_text=$(echo "$login_banner_text" | sed 's/\[\\s\\n\]+/ /g')
# 3 - Adds newlines. (Transforms "(?:\[\\n\]+|(?:\\n)+)" into "\n")
login_banner_text=$(echo "$login_banner_text" | sed 's/(?:\[\\n\]+|(?:\\\\n)+)/\n/g')
# 4 - Remove any leftover backslash. (From any parethesis in the banner, for example).
login_banner_text=$(echo "$login_banner_text" | sed 's/\\//g')
formatted=$(echo "$login_banner_text" | fold -sw 80)

cat <<EOF >/etc/issue.net
$formatted
EOF

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Modify the System Message of the Day Banner   [ref]

To configure the system message banner edit /etc/motd. Replace the default text with a message compliant with the local site policy or a legal disclaimer. The DoD required text is either:

You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions:
-The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations.
-At any time, the USG may inspect and seize data stored on this IS.
-Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose.
-This IS includes security measures (e.g., authentication and access controls) to protect USG interests -- not for your personal benefit or privacy.
-Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details.

OR:

I've read & consent to terms in IS user agreem't.
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.

System use notifications are required only for access via login interfaces with human users and are not required when such human interfaces do not exist.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_banner_etc_motd
Identifiers and References

References:  1.7.1


Complexity:low
Disruption:medium
- name: XCCDF Value login_banner_text # promote to variable
  set_fact:
    login_banner_text: !!str ^(Authorized[\s\n]+uses[\s\n]+only\.[\s\n]+All[\s\n]+activity[\s\n]+may[\s\n]+be[\s\n]+monitored[\s\n]+and[\s\n]+reported\.|^(?!.*(\\|fedora|rhel|sle|ubuntu)).*)$
  tags:
    - always

- name: Modify the System Message of the Day Banner - ensure correct banner
  copy:
    dest: /etc/motd
    content: '{{ login_banner_text | regex_replace("^\^(.*)\$$", "\1") | regex_replace("^\((.*\.)\|.*\)$",
      "\1") | regex_replace("\[\\s\\n\]\+"," ") | regex_replace("\(\?:\[\\n\]\+\|\(\?:\\\\n\)\+\)",
      "\n") | regex_replace("\\", "") | wordwrap() }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - banner_etc_motd
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - unknown_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

login_banner_text='^(Authorized[\s\n]+uses[\s\n]+only\.[\s\n]+All[\s\n]+activity[\s\n]+may[\s\n]+be[\s\n]+monitored[\s\n]+and[\s\n]+reported\.|^(?!.*(\\|fedora|rhel|sle|ubuntu)).*)$'


# Multiple regexes transform the banner regex into a usable banner
# 0 - Remove anchors around the banner text
login_banner_text=$(echo "$login_banner_text" | sed 's/^\^\(.*\)\$$/\1/g')
# 1 - Keep only the first banners if there are multiple
#    (dod_banners contains the long and short banner)
login_banner_text=$(echo "$login_banner_text" | sed 's/^(\(.*\.\)|.*)$/\1/g')
# 2 - Add spaces ' '. (Transforms regex for "space or newline" into a " ")
login_banner_text=$(echo "$login_banner_text" | sed 's/\[\\s\\n\]+/ /g')
# 3 - Adds newlines. (Transforms "(?:\[\\n\]+|(?:\\n)+)" into "\n")
login_banner_text=$(echo "$login_banner_text" | sed 's/(?:\[\\n\]+|(?:\\\\n)+)/\n/g')
# 4 - Remove any leftover backslash. (From any parethesis in the banner, for example).
login_banner_text=$(echo "$login_banner_text" | sed 's/\\//g')
formatted=$(echo "$login_banner_text" | fold -sw 80)

cat <<EOF >/etc/motd
$formatted
EOF

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Verify Group Ownership of System Login Banner   [ref]

To properly set the group owner of /etc/issue, run the command: 
$ sudo chgrp root /etc/issue
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper group ownership will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_etc_issue
Identifiers and References

References:  1.7.5


Complexity:low
Disruption:low
Strategy:configure
- name: Test for existence /etc/issue
  stat:
    path: /etc/issue
  register: file_exists
  tags:
  - configure_strategy
  - file_groupowner_etc_issue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/issue
  file:
    path: /etc/issue
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_groupowner_etc_issue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure



chgrp 0 /etc/issue

Rule   Verify Group Ownership of System Login Banner for Remote Connections   [ref]

To properly set the group owner of /etc/issue.net, run the command: 
$ sudo chgrp root /etc/issue.net
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper group ownership will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_etc_issue_net
Identifiers and References

References:  1.7.6


Complexity:low
Disruption:low
Strategy:configure
- name: Test for existence /etc/issue.net
  stat:
    path: /etc/issue.net
  register: file_exists
  tags:
  - configure_strategy
  - file_groupowner_etc_issue_net
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/issue.net
  file:
    path: /etc/issue.net
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_groupowner_etc_issue_net
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure



chgrp 0 /etc/issue.net

Rule   Verify Group Ownership of Message of the Day Banner   [ref]

To properly set the group owner of /etc/motd, run the command: 
$ sudo chgrp root /etc/motd
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper group ownership will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_etc_motd
Identifiers and References

References:  1.7.4


Complexity:low
Disruption:low
Strategy:configure
- name: Test for existence /etc/motd
  stat:
    path: /etc/motd
  register: file_exists
  tags:
  - configure_strategy
  - file_groupowner_etc_motd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /etc/motd
  file:
    path: /etc/motd
    group: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_groupowner_etc_motd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure



chgrp 0 /etc/motd

Rule   Verify ownership of System Login Banner   [ref]

To properly set the owner of /etc/issue, run the command: 
$ sudo chown root /etc/issue
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper ownership will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_etc_issue
Identifiers and References

References:  1.7.5


Complexity:low
Disruption:low
Strategy:configure
- name: Test for existence /etc/issue
  stat:
    path: /etc/issue
  register: file_exists
  tags:
  - configure_strategy
  - file_owner_etc_issue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/issue
  file:
    path: /etc/issue
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_owner_etc_issue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure



chown 0 /etc/issue

Rule   Verify ownership of System Login Banner for Remote Connections   [ref]

To properly set the owner of /etc/issue.net, run the command: 
$ sudo chown root /etc/issue.net
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper ownership will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_etc_issue_net
Identifiers and References

References:  1.7.6


Complexity:low
Disruption:low
Strategy:configure
- name: Test for existence /etc/issue.net
  stat:
    path: /etc/issue.net
  register: file_exists
  tags:
  - configure_strategy
  - file_owner_etc_issue_net
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/issue.net
  file:
    path: /etc/issue.net
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_owner_etc_issue_net
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure



chown 0 /etc/issue.net

Rule   Verify ownership of Message of the Day Banner   [ref]

To properly set the owner of /etc/motd, run the command: 
$ sudo chown root /etc/motd
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper ownership will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_etc_motd
Identifiers and References

References:  1.7.4


Complexity:low
Disruption:low
Strategy:configure
- name: Test for existence /etc/motd
  stat:
    path: /etc/motd
  register: file_exists
  tags:
  - configure_strategy
  - file_owner_etc_motd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /etc/motd
  file:
    path: /etc/motd
    owner: '0'
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_owner_etc_motd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure



chown 0 /etc/motd

Rule   Verify permissions on System Login Banner   [ref]

To properly set the permissions of /etc/issue, run the command: 
$ sudo chmod 0644 /etc/issue
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper permissions will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_etc_issue
Identifiers and References

References:  1.7.5


Complexity:low
Disruption:low
Strategy:configure
- name: Test for existence /etc/issue
  stat:
    path: /etc/issue
  register: file_exists
  tags:
  - configure_strategy
  - file_permissions_etc_issue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwt on /etc/issue
  file:
    path: /etc/issue
    mode: u-xs,g-xws,o-xwt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_permissions_etc_issue
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure




chmod u-xs,g-xws,o-xwt /etc/issue

Rule   Verify permissions on System Login Banner for Remote Connections   [ref]

To properly set the permissions of /etc/issue.net, run the command: 
$ sudo chmod 0644 /etc/issue.net
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper permissions will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_etc_issue_net
Identifiers and References

References:  1.7.6


Complexity:low
Disruption:low
Strategy:configure
- name: Test for existence /etc/issue.net
  stat:
    path: /etc/issue.net
  register: file_exists
  tags:
  - configure_strategy
  - file_permissions_etc_issue_net
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwt on /etc/issue.net
  file:
    path: /etc/issue.net
    mode: u-xs,g-xws,o-xwt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_permissions_etc_issue_net
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure




chmod u-xs,g-xws,o-xwt /etc/issue.net

Rule   Verify permissions on Message of the Day Banner   [ref]

To properly set the permissions of /etc/motd, run the command: 
$ sudo chmod 0644 /etc/motd
Rationale:
Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.
Proper permissions will ensure that only root user can modify the banner.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_etc_motd
Identifiers and References

References:  1.7.4


Complexity:low
Disruption:low
Strategy:configure
- name: Test for existence /etc/motd
  stat:
    path: /etc/motd
  register: file_exists
  tags:
  - configure_strategy
  - file_permissions_etc_motd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xws,o-xwt on /etc/motd
  file:
    path: /etc/motd
    mode: u-xs,g-xws,o-xwt
  when: file_exists.stat is defined and file_exists.stat.exists
  tags:
  - configure_strategy
  - file_permissions_etc_motd
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure




chmod u-xs,g-xws,o-xwt /etc/motd
Group   Protect Accounts by Configuring PAM   Group contains 4 groups and 5 rules
[ref]   PAM, or Pluggable Authentication Modules, is a system which implements modular authentication for Linux programs. PAM provides a flexible and configurable architecture for authentication, and it should be configured to minimize exposure to unnecessary risk. This section contains guidance on how to accomplish that.

PAM is implemented as a set of shared objects which are loaded and invoked whenever an application wishes to authenticate a user. Typically, the application must be running as root in order to take advantage of PAM, because PAM's modules often need to be able to access sensitive stores of account information, such as /etc/shadow. Traditional privileged network listeners (e.g. sshd) or SUID programs (e.g. sudo) already meet this requirement. An SUID root application, userhelper, is provided so that programs which are not SUID or privileged themselves can still take advantage of PAM.

PAM looks in the directory /etc/pam.d for application-specific configuration information. For instance, if the program login attempts to authenticate a user, then PAM's libraries follow the instructions in the file /etc/pam.d/login to determine what actions should be taken.

One very important file in /etc/pam.d is /etc/pam.d/system-auth. This file, which is included by many other PAM configuration files, defines 'default' system authentication measures. Modifying this file is a good way to make far-reaching authentication changes, for instance when implementing a centralized authentication service.
Warning:  Be careful when making changes to PAM's configuration files. The syntax for these files is complex, and modifications can have unexpected consequences. The default configurations shipped with applications should be sufficient for most users.
Warning:  Running authconfig or system-config-authentication will re-write the PAM configuration files, destroying any manually made changes and replacing them with a series of system defaults. One reference to the configuration file syntax can be found at https://fossies.org/linux/Linux-PAM-docs/doc/sag/Linux-PAM_SAG.pdf.
Group   Set Lockouts for Failed Password Attempts   Group contains 2 rules
[ref]   The pam_faillock PAM module provides the capability to lock out user accounts after a number of failed login attempts. Its documentation is available in /usr/share/doc/pam-VERSION/txts/README.pam_faillock.

Warning:  Locking out user accounts presents the risk of a denial-of-service attack. The lockout policy must weigh whether the risk of such a denial-of-service attack outweighs the benefits of thwarting password guessing attacks.

Rule   Limit Password Reuse: password-auth   [ref]

Do not allow users to reuse recent passwords. This can be accomplished by using the remember option for the pam_pwhistory PAM module.

In the file /etc/pam.d/password-auth, make sure the parameter remember is present and it has a value equal to or greater than 5

For example: 
password requisite pam_pwhistory.so use_authtok remember=5
Warning:  If the system relies on authselect tool to manage PAM settings, the remediation will also use authselect tool. However, if any manual modification was made in PAM files, the authselect integrity check will fail and the remediation will be aborted in order to preserve intentional changes. In this case, an informative message will be shown in the remediation report.
Warning:  Newer versions of authselect contain an authselect feature to easily and properly enable pam_pwhistory.so module. If this feature is not yet available in your system, an authselect custom profile must be used to avoid integrity issues in PAM files.
Rationale:
Preventing re-use of previous passwords helps ensure that a compromised password is not re-used by a user.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_pwhistory_remember_password_auth
Identifiers and References

References:  BP28(R18), 1, 12, 15, 16, 5, 5.6.2.1.1, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10, 3.5.8, CCI-000200, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3, IA-5(f), IA-5(1)(e), PR.AC-1, PR.AC-6, PR.AC-7, Req-8.2.5, SRG-OS-000077-GPOS-00045, SRG-OS-000077-VMM-000440, 5.4.4, SV-204422r880836_rule


Complexity:low
Disruption:medium
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_password_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
- name: XCCDF Value var_password_pam_remember # promote to variable
  set_fact:
    var_password_pam_remember: !!str 5
  tags:
    - always
- name: XCCDF Value var_password_pam_remember_control_flag # promote to variable
  set_fact:
    var_password_pam_remember_control_flag: !!str requisite
  tags:
    - always

- name: 'Limit Password Reuse: password-auth - Check if system relies on authselect
    tool'
  ansible.builtin.stat:
    path: /usr/bin/authselect
  register: result_authselect_present
  when: '"pam" in ansible_facts.packages'
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_password_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed

- name: 'Limit Password Reuse: password-auth - Collect the available authselect features'
  ansible.builtin.command:
    cmd: authselect list-features minimal
  register: result_authselect_available_features
  changed_when: false
  when:
  - '"pam" in ansible_facts.packages'
  - result_authselect_present.stat.exists
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_password_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed

- name: 'Limit Password Reuse: password-auth - Enable pam_pwhistory.so using authselect
    feature'
  block:

  - name: 'Limit Password Reuse: password-auth - Check integrity of authselect current
      profile'
    ansible.builtin.command:
      cmd: authselect check
    register: result_authselect_check_cmd
    changed_when: false
    ignore_errors: true

  - name: 'Limit Password Reuse: password-auth - Informative message based on the
      authselect integrity check result'
    ansible.builtin.assert:
      that:
      - result_authselect_check_cmd is success
      fail_msg:
      - authselect integrity check failed. Remediation aborted!
      - This remediation could not be applied because an authselect profile was not
        selected or the selected profile is not intact.
      - It is not recommended to manually edit the PAM files when authselect tool
        is available.
      - In cases where the default authselect profile does not cover a specific demand,
        a custom authselect profile is recommended.
      success_msg:
      - authselect integrity check passed

  - name: 'Limit Password Reuse: password-auth - Get authselect current features'
    ansible.builtin.shell:
      cmd: authselect current | tail -n+3 | awk '{ print $2 }'
    register: result_authselect_features
    changed_when: false
    when:
    - result_authselect_check_cmd is success

  - name: 'Limit Password Reuse: password-auth - Ensure "with-pwhistory" feature is
      enabled using authselect tool'
    ansible.builtin.command:
      cmd: authselect enable-feature with-pwhistory
    register: result_authselect_enable_feature_cmd
    when:
    - result_authselect_check_cmd is success
    - result_authselect_features.stdout is not search("with-pwhistory")

  - name: 'Limit Password Reuse: password-auth - Ensure authselect changes are applied'
    ansible.builtin.command:
      cmd: authselect apply-changes -b
    when:
    - result_authselect_enable_feature_cmd is not skipped
    - result_authselect_enable_feature_cmd is success
  when:
  - '"pam" in ansible_facts.packages'
  - result_authselect_present.stat.exists
  - result_authselect_available_features.stdout is search("with-pwhistory")
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_password_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed

- name: 'Limit Password Reuse: password-auth - Enable pam_pwhistory.so in appropriate
    PAM files'
  block:

  - name: 'Limit Password Reuse: password-auth - Define the PAM file to be edited
      as a local fact'
    ansible.builtin.set_fact:
      pam_file_path: /etc/pam.d/password-auth

  - name: 'Limit Password Reuse: password-auth - Check if system relies on authselect
      tool'
    ansible.builtin.stat:
      path: /usr/bin/authselect
    register: result_authselect_present

  - name: 'Limit Password Reuse: password-auth - Ensure authselect custom profile
      is used if authselect is present'
    block:

    - name: 'Limit Password Reuse: password-auth - Check integrity of authselect current
        profile'
      ansible.builtin.command:
        cmd: authselect check
      register: result_authselect_check_cmd
      changed_when: false
      ignore_errors: true

    - name: 'Limit Password Reuse: password-auth - Informative message based on the
        authselect integrity check result'
      ansible.builtin.assert:
        that:
        - result_authselect_check_cmd is success
        fail_msg:
        - authselect integrity check failed. Remediation aborted!
        - This remediation could not be applied because an authselect profile was
          not selected or the selected profile is not intact.
        - It is not recommended to manually edit the PAM files when authselect tool
          is available.
        - In cases where the default authselect profile does not cover a specific
          demand, a custom authselect profile is recommended.
        success_msg:
        - authselect integrity check passed

    - name: 'Limit Password Reuse: password-auth - Get authselect current profile'
      ansible.builtin.shell:
        cmd: authselect current -r | awk '{ print $1 }'
      register: result_authselect_profile
      changed_when: false
      when:
      - result_authselect_check_cmd is success

    - name: 'Limit Password Reuse: password-auth - Define the current authselect profile
        as a local fact'
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: '{{ result_authselect_profile.stdout }}'
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is match("custom/")

    - name: 'Limit Password Reuse: password-auth - Define the new authselect custom
        profile as a local fact'
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: custom/hardening
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is not match("custom/")

    - name: 'Limit Password Reuse: password-auth - Get authselect current features
        to also enable them in the custom profile'
      ansible.builtin.shell:
        cmd: authselect current | tail -n+3 | awk '{ print $2 }'
      register: result_authselect_features
      changed_when: false
      when:
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")

    - name: 'Limit Password Reuse: password-auth - Check if any custom profile with
        the same name was already created'
      ansible.builtin.stat:
        path: /etc/authselect/{{ authselect_custom_profile }}
      register: result_authselect_custom_profile_present
      changed_when: false
      when:
      - authselect_current_profile is not match("custom/")

    - name: 'Limit Password Reuse: password-auth - Create an authselect custom profile
        based on the current profile'
      ansible.builtin.command:
        cmd: authselect create-profile hardening -b {{ authselect_current_profile
          }}
      when:
      - result_authselect_check_cmd is success
      - authselect_current_profile is not match("custom/")
      - not result_authselect_custom_profile_present.stat.exists

    - name: 'Limit Password Reuse: password-auth - Ensure authselect changes are applied'
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=before-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: 'Limit Password Reuse: password-auth - Ensure the authselect custom profile
        is selected'
      ansible.builtin.command:
        cmd: authselect select {{ authselect_custom_profile }}
      register: result_pam_authselect_select_profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: 'Limit Password Reuse: password-auth - Restore the authselect features
        in the custom profile'
      ansible.builtin.command:
        cmd: authselect enable-feature {{ item }}
      loop: '{{ result_authselect_features.stdout_lines }}'
      register: result_pam_authselect_restore_features
      when:
      - result_authselect_profile is not skipped
      - result_authselect_features is not skipped
      - result_pam_authselect_select_profile is not skipped

    - name: 'Limit Password Reuse: password-auth - Ensure authselect changes are applied'
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=after-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - result_pam_authselect_restore_features is not skipped

    - name: 'Limit Password Reuse: password-auth - Change the PAM file to be edited
        according to the custom authselect profile'
      ansible.builtin.set_fact:
        pam_file_path: /etc/authselect/{{ authselect_custom_profile }}/{{ pam_file_path
          | basename }}
    when:
    - result_authselect_present.stat.exists

  - name: 'Limit Password Reuse: password-auth - Check if expected PAM module line
      is present in {{ pam_file_path }}'
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      regexp: ^\s*password\s+{{ var_password_pam_remember_control_flag.split(",")[0]
        }}\s+pam_pwhistory.so\s*.*
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_line_present

  - name: 'Limit Password Reuse: password-auth - Include or update the PAM module
      line in {{ pam_file_path }}'
    block:

    - name: 'Limit Password Reuse: password-auth - Check if required PAM module line
        is present in {{ pam_file_path }} with different control'
      ansible.builtin.lineinfile:
        path: '{{ pam_file_path }}'
        regexp: ^\s*password\s+.*\s+pam_pwhistory.so\s*
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_line_other_control_present

    - name: 'Limit Password Reuse: password-auth - Ensure the correct control for
        the required PAM module line in {{ pam_file_path }}'
      ansible.builtin.replace:
        dest: '{{ pam_file_path }}'
        regexp: ^(\s*password\s+).*(\bpam_pwhistory.so.*)
        replace: \1{{ var_password_pam_remember_control_flag.split(",")[0] }} \2
      register: result_pam_module_edit
      when:
      - result_pam_line_other_control_present.found == 1

    - name: 'Limit Password Reuse: password-auth - Ensure the required PAM module
        line is included in {{ pam_file_path }}'
      ansible.builtin.lineinfile:
        dest: '{{ pam_file_path }}'
        insertafter: ^password.*requisite.*pam_pwquality\.so
        line: password    {{ var_password_pam_remember_control_flag.split(",")[0]
          }}    pam_pwhistory.so
      register: result_pam_module_add
      when:
      - result_pam_line_other_control_present.found == 0 or result_pam_line_other_control_present.found
        > 1

    - name: 'Limit Password Reuse: password-auth - Ensure authselect changes are applied'
      ansible.builtin.command:
        cmd: authselect apply-changes -b
      when: |
        result_authselect_present is defined and result_authselect_present.stat.exists and ((result_pam_module_add is defined and result_pam_module_add.changed) or (result_pam_module_edit is defined and result_pam_module_edit.changed))
    when:
    - result_pam_line_present.found is defined
    - result_pam_line_present.found == 0
  when:
  - '"pam" in ansible_facts.packages'
  - |
    (result_authselect_available_features.stdout is defined and result_authselect_available_features.stdout is not search("with-pwhistory")) or result_authselect_available_features is not defined
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_password_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed

- name: 'Limit Password Reuse: password-auth - Check the presence of /etc/security/pwhistory.conf
    file'
  ansible.builtin.stat:
    path: /etc/security/pwhistory.conf
  register: result_pwhistory_conf_check
  when: '"pam" in ansible_facts.packages'
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_password_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed

- name: 'Limit Password Reuse: password-auth - pam_pwhistory.so parameters are configured
    in /etc/security/pwhistory.conf file'
  block:

  - name: 'Limit Password Reuse: password-auth - Ensure the pam_pwhistory.so remember
      parameter in /etc/security/pwhistory.conf'
    ansible.builtin.lineinfile:
      path: /etc/security/pwhistory.conf
      regexp: ^\s*remember\s*=
      line: remember = {{ var_password_pam_remember }}
      state: present

  - name: 'Limit Password Reuse: password-auth - Ensure the pam_pwhistory.so remember
      parameter is removed from PAM files'
    block:

    - name: 'Limit Password Reuse: password-auth - Check if /etc/pam.d/password-auth
        file is present'
      ansible.builtin.stat:
        path: /etc/pam.d/password-auth
      register: result_pam_file_present

    - name: 'Limit Password Reuse: password-auth - Check the proper remediation for
        the system'
      block:

      - name: 'Limit Password Reuse: password-auth - Define the PAM file to be edited
          as a local fact'
        ansible.builtin.set_fact:
          pam_file_path: /etc/pam.d/password-auth

      - name: 'Limit Password Reuse: password-auth - Check if system relies on authselect
          tool'
        ansible.builtin.stat:
          path: /usr/bin/authselect
        register: result_authselect_present

      - name: 'Limit Password Reuse: password-auth - Ensure authselect custom profile
          is used if authselect is present'
        block:

        - name: 'Limit Password Reuse: password-auth - Check integrity of authselect
            current profile'
          ansible.builtin.command:
            cmd: authselect check
          register: result_authselect_check_cmd
          changed_when: false
          ignore_errors: true

        - name: 'Limit Password Reuse: password-auth - Informative message based on
            the authselect integrity check result'
          ansible.builtin.assert:
            that:
            - result_authselect_check_cmd is success
            fail_msg:
            - authselect integrity check failed. Remediation aborted!
            - This remediation could not be applied because an authselect profile
              was not selected or the selected profile is not intact.
            - It is not recommended to manually edit the PAM files when authselect
              tool is available.
            - In cases where the default authselect profile does not cover a specific
              demand, a custom authselect profile is recommended.
            success_msg:
            - authselect integrity check passed

        - name: 'Limit Password Reuse: password-auth - Get authselect current profile'
          ansible.builtin.shell:
            cmd: authselect current -r | awk '{ print $1 }'
          register: result_authselect_profile
          changed_when: false
          when:
          - result_authselect_check_cmd is success

        - name: 'Limit Password Reuse: password-auth - Define the current authselect
            profile as a local fact'
          ansible.builtin.set_fact:
            authselect_current_profile: '{{ result_authselect_profile.stdout }}'
            authselect_custom_profile: '{{ result_authselect_profile.stdout }}'
          when:
          - result_authselect_profile is not skipped
          - result_authselect_profile.stdout is match("custom/")

        - name: 'Limit Password Reuse: password-auth - Define the new authselect custom
            profile as a local fact'
          ansible.builtin.set_fact:
            authselect_current_profile: '{{ result_authselect_profile.stdout }}'
            authselect_custom_profile: custom/hardening
          when:
          - result_authselect_profile is not skipped
          - result_authselect_profile.stdout is not match("custom/")

        - name: 'Limit Password Reuse: password-auth - Get authselect current features
            to also enable them in the custom profile'
          ansible.builtin.shell:
            cmd: authselect current | tail -n+3 | awk '{ print $2 }'
          register: result_authselect_features
          changed_when: false
          when:
          - result_authselect_profile is not skipped
          - authselect_current_profile is not match("custom/")

        - name: 'Limit Password Reuse: password-auth - Check if any custom profile
            with the same name was already created'
          ansible.builtin.stat:
            path: /etc/authselect/{{ authselect_custom_profile }}
          register: result_authselect_custom_profile_present
          changed_when: false
          when:
          - authselect_current_profile is not match("custom/")

        - name: 'Limit Password Reuse: password-auth - Create an authselect custom
            profile based on the current profile'
          ansible.builtin.command:
            cmd: authselect create-profile hardening -b {{ authselect_current_profile
              }}
          when:
          - result_authselect_check_cmd is success
          - authselect_current_profile is not match("custom/")
          - not result_authselect_custom_profile_present.stat.exists

        - name: 'Limit Password Reuse: password-auth - Ensure authselect changes are
            applied'
          ansible.builtin.command:
            cmd: authselect apply-changes -b --backup=before-hardening-custom-profile
          when:
          - result_authselect_check_cmd is success
          - result_authselect_profile is not skipped
          - authselect_current_profile is not match("custom/")
          - authselect_custom_profile is not match(authselect_current_profile)

        - name: 'Limit Password Reuse: password-auth - Ensure the authselect custom
            profile is selected'
          ansible.builtin.command:
            cmd: authselect select {{ authselect_custom_profile }}
          register: result_pam_authselect_select_profile
          when:
          - result_authselect_check_cmd is success
          - result_authselect_profile is not skipped
          - authselect_current_profile is not match("custom/")
          - authselect_custom_profile is not match(authselect_current_profile)

        - name: 'Limit Password Reuse: password-auth - Restore the authselect features
            in the custom profile'
          ansible.builtin.command:
            cmd: authselect enable-feature {{ item }}
          loop: '{{ result_authselect_features.stdout_lines }}'
          register: result_pam_authselect_restore_features
          when:
          - result_authselect_profile is not skipped
          - result_authselect_features is not skipped
          - result_pam_authselect_select_profile is not skipped

        - name: 'Limit Password Reuse: password-auth - Ensure authselect changes are
            applied'
          ansible.builtin.command:
            cmd: authselect apply-changes -b --backup=after-hardening-custom-profile
          when:
          - result_authselect_check_cmd is success
          - result_authselect_profile is not skipped
          - result_pam_authselect_restore_features is not skipped

        - name: 'Limit Password Reuse: password-auth - Change the PAM file to be edited
            according to the custom authselect profile'
          ansible.builtin.set_fact:
            pam_file_path: /etc/authselect/{{ authselect_custom_profile }}/{{ pam_file_path
              | basename }}
        when:
        - result_authselect_present.stat.exists

      - name: 'Limit Password Reuse: password-auth - Ensure the "remember" option
          from "pam_pwhistory.so" is not present in {{ pam_file_path }}'
        ansible.builtin.replace:
          dest: '{{ pam_file_path }}'
          regexp: (.*password.*pam_pwhistory.so.*)\bremember\b=?[0-9a-zA-Z]*(.*)
          replace: \1\2
        register: result_pam_option_removal

      - name: 'Limit Password Reuse: password-auth - Ensure authselect changes are
          applied'
        ansible.builtin.command:
          cmd: authselect apply-changes -b
        when:
        - result_authselect_present.stat.exists
        - result_pam_option_removal is changed
      when:
      - result_pam_file_present.stat.exists
  when:
  - '"pam" in ansible_facts.packages'
  - result_pwhistory_conf_check.stat.exists
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_password_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed

- name: 'Limit Password Reuse: password-auth - pam_pwhistory.so parameters are configured
    in PAM files'
  block:

  - name: 'Limit Password Reuse: password-auth - Define the PAM file to be edited
      as a local fact'
    ansible.builtin.set_fact:
      pam_file_path: /etc/pam.d/password-auth

  - name: 'Limit Password Reuse: password-auth - Check if system relies on authselect
      tool'
    ansible.builtin.stat:
      path: /usr/bin/authselect
    register: result_authselect_present

  - name: 'Limit Password Reuse: password-auth - Ensure authselect custom profile
      is used if authselect is present'
    block:

    - name: 'Limit Password Reuse: password-auth - Check integrity of authselect current
        profile'
      ansible.builtin.command:
        cmd: authselect check
      register: result_authselect_check_cmd
      changed_when: false
      ignore_errors: true

    - name: 'Limit Password Reuse: password-auth - Informative message based on the
        authselect integrity check result'
      ansible.builtin.assert:
        that:
        - result_authselect_check_cmd is success
        fail_msg:
        - authselect integrity check failed. Remediation aborted!
        - This remediation could not be applied because an authselect profile was
          not selected or the selected profile is not intact.
        - It is not recommended to manually edit the PAM files when authselect tool
          is available.
        - In cases where the default authselect profile does not cover a specific
          demand, a custom authselect profile is recommended.
        success_msg:
        - authselect integrity check passed

    - name: 'Limit Password Reuse: password-auth - Get authselect current profile'
      ansible.builtin.shell:
        cmd: authselect current -r | awk '{ print $1 }'
      register: result_authselect_profile
      changed_when: false
      when:
      - result_authselect_check_cmd is success

    - name: 'Limit Password Reuse: password-auth - Define the current authselect profile
        as a local fact'
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: '{{ result_authselect_profile.stdout }}'
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is match("custom/")

    - name: 'Limit Password Reuse: password-auth - Define the new authselect custom
        profile as a local fact'
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: custom/hardening
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is not match("custom/")

    - name: 'Limit Password Reuse: password-auth - Get authselect current features
        to also enable them in the custom profile'
      ansible.builtin.shell:
        cmd: authselect current | tail -n+3 | awk '{ print $2 }'
      register: result_authselect_features
      changed_when: false
      when:
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")

    - name: 'Limit Password Reuse: password-auth - Check if any custom profile with
        the same name was already created'
      ansible.builtin.stat:
        path: /etc/authselect/{{ authselect_custom_profile }}
      register: result_authselect_custom_profile_present
      changed_when: false
      when:
      - authselect_current_profile is not match("custom/")

    - name: 'Limit Password Reuse: password-auth - Create an authselect custom profile
        based on the current profile'
      ansible.builtin.command:
        cmd: authselect create-profile hardening -b {{ authselect_current_profile
          }}
      when:
      - result_authselect_check_cmd is success
      - authselect_current_profile is not match("custom/")
      - not result_authselect_custom_profile_present.stat.exists

    - name: 'Limit Password Reuse: password-auth - Ensure authselect changes are applied'
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=before-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: 'Limit Password Reuse: password-auth - Ensure the authselect custom profile
        is selected'
      ansible.builtin.command:
        cmd: authselect select {{ authselect_custom_profile }}
      register: result_pam_authselect_select_profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: 'Limit Password Reuse: password-auth - Restore the authselect features
        in the custom profile'
      ansible.builtin.command:
        cmd: authselect enable-feature {{ item }}
      loop: '{{ result_authselect_features.stdout_lines }}'
      register: result_pam_authselect_restore_features
      when:
      - result_authselect_profile is not skipped
      - result_authselect_features is not skipped
      - result_pam_authselect_select_profile is not skipped

    - name: 'Limit Password Reuse: password-auth - Ensure authselect changes are applied'
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=after-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - result_pam_authselect_restore_features is not skipped

    - name: 'Limit Password Reuse: password-auth - Change the PAM file to be edited
        according to the custom authselect profile'
      ansible.builtin.set_fact:
        pam_file_path: /etc/authselect/{{ authselect_custom_profile }}/{{ pam_file_path
          | basename }}
    when:
    - result_authselect_present.stat.exists

  - name: 'Limit Password Reuse: password-auth - Check if expected PAM module line
      is present in {{ pam_file_path }}'
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      regexp: ^\s*password\s+requisite\s+pam_pwhistory.so\s*.*
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_line_present

  - name: 'Limit Password Reuse: password-auth - Include or update the PAM module
      line in {{ pam_file_path }}'
    block:

    - name: 'Limit Password Reuse: password-auth - Check if required PAM module line
        is present in {{ pam_file_path }} with different control'
      ansible.builtin.lineinfile:
        path: '{{ pam_file_path }}'
        regexp: ^\s*password\s+.*\s+pam_pwhistory.so\s*
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_line_other_control_present

    - name: 'Limit Password Reuse: password-auth - Ensure the correct control for
        the required PAM module line in {{ pam_file_path }}'
      ansible.builtin.replace:
        dest: '{{ pam_file_path }}'
        regexp: ^(\s*password\s+).*(\bpam_pwhistory.so.*)
        replace: \1requisite \2
      register: result_pam_module_edit
      when:
      - result_pam_line_other_control_present.found == 1

    - name: 'Limit Password Reuse: password-auth - Ensure the required PAM module
        line is included in {{ pam_file_path }}'
      ansible.builtin.lineinfile:
        dest: '{{ pam_file_path }}'
        line: password    requisite    pam_pwhistory.so
      register: result_pam_module_add
      when:
      - result_pam_line_other_control_present.found == 0 or result_pam_line_other_control_present.found
        > 1

    - name: 'Limit Password Reuse: password-auth - Ensure authselect changes are applied'
      ansible.builtin.command:
        cmd: authselect apply-changes -b
      when: |
        result_authselect_present is defined and result_authselect_present.stat.exists and ((result_pam_module_add is defined and result_pam_module_add.changed) or (result_pam_module_edit is defined and result_pam_module_edit.changed))
    when:
    - result_pam_line_present.found is defined
    - result_pam_line_present.found == 0

  - name: 'Limit Password Reuse: password-auth - Check if the required PAM module
      option is present in {{ pam_file_path }}'
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      regexp: ^\s*password\s+requisite\s+pam_pwhistory.so\s*.*\sremember\b
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_module_remember_option_present

  - name: 'Limit Password Reuse: password-auth - Ensure the "remember" PAM option
      for "pam_pwhistory.so" is included in {{ pam_file_path }}'
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      backrefs: true
      regexp: ^(\s*password\s+requisite\s+pam_pwhistory.so.*)
      line: \1 remember={{ var_password_pam_remember }}
      state: present
    register: result_pam_remember_add
    when:
    - result_pam_module_remember_option_present.found == 0

  - name: 'Limit Password Reuse: password-auth - Ensure the required value for "remember"
      PAM option from "pam_pwhistory.so" in {{ pam_file_path }}'
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      backrefs: true
      regexp: ^(\s*password\s+requisite\s+pam_pwhistory.so\s+.*)(remember)=[0-9a-zA-Z]+\s*(.*)
      line: \1\2={{ var_password_pam_remember }} \3
    register: result_pam_remember_edit
    when:
    - result_pam_module_remember_option_present.found > 0

  - name: 'Limit Password Reuse: password-auth - Ensure authselect changes are applied'
    ansible.builtin.command:
      cmd: authselect apply-changes -b
    when:
    - result_authselect_present.stat.exists
    - (result_pam_remember_add is defined and result_pam_remember_add.changed) or
      (result_pam_remember_edit is defined and result_pam_remember_edit.changed)
  when:
  - '"pam" in ansible_facts.packages'
  - not result_pwhistory_conf_check.stat.exists
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_password_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed


# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_password_pam_remember='5'
var_password_pam_remember_control_flag='requisite'


var_password_pam_remember_control_flag="$(echo $var_password_pam_remember_control_flag | cut -d \, -f 1)"

if [ -f /usr/bin/authselect ]; then
    if authselect list-features minimal | grep -q with-pwhistory; then
        if ! authselect check; then
        echo "
        authselect integrity check failed. Remediation aborted!
        This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
        It is not recommended to manually edit the PAM files when authselect tool is available.
        In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
        exit 1
        fi
        authselect enable-feature with-pwhistory

        authselect apply-changes -b
    else
        
        if ! authselect check; then
        echo "
        authselect integrity check failed. Remediation aborted!
        This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
        It is not recommended to manually edit the PAM files when authselect tool is available.
        In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
        exit 1
        fi

        CURRENT_PROFILE=$(authselect current -r | awk '{ print $1 }')
        # If not already in use, a custom profile is created preserving the enabled features.
        if [[ ! $CURRENT_PROFILE == custom/* ]]; then
            ENABLED_FEATURES=$(authselect current | tail -n+3 | awk '{ print $2 }')
            authselect create-profile hardening -b $CURRENT_PROFILE
            CURRENT_PROFILE="custom/hardening"
            
            authselect apply-changes -b --backup=before-hardening-custom-profile
            authselect select $CURRENT_PROFILE
            for feature in $ENABLED_FEATURES; do
                authselect enable-feature $feature;
            done
            
            authselect apply-changes -b --backup=after-hardening-custom-profile
        fi
        PAM_FILE_NAME=$(basename "/etc/pam.d/password-auth")
        PAM_FILE_PATH="/etc/authselect/$CURRENT_PROFILE/$PAM_FILE_NAME"

        authselect apply-changes -b
        if ! grep -qP '^\s*password\s+'"$var_password_pam_remember_control_flag"'\s+pam_pwhistory.so\s*.*' "$PAM_FILE_PATH"; then
            # Line matching group + control + module was not found. Check group + module.
            if [ "$(grep -cP '^\s*password\s+.*\s+pam_pwhistory.so\s*' "$PAM_FILE_PATH")" -eq 1 ]; then
                # The control is updated only if one single line matches.
                sed -i -E --follow-symlinks 's/^(\s*password\s+).*(\bpam_pwhistory.so.*)/\1'"$var_password_pam_remember_control_flag"' \2/' "$PAM_FILE_PATH"
            else
                LAST_MATCH_LINE=$(grep -nP "^password.*requisite.*pam_pwquality\.so" "$PAM_FILE_PATH" | tail -n 1 | cut -d: -f 1)
                if [ ! -z $LAST_MATCH_LINE ]; then
                    sed -i --follow-symlinks $LAST_MATCH_LINE' a password     '"$var_password_pam_remember_control_flag"'    pam_pwhistory.so' "$PAM_FILE_PATH"
                else
                    echo 'password    '"$var_password_pam_remember_control_flag"'    pam_pwhistory.so' >> "$PAM_FILE_PATH"
                fi
            fi
        fi
    fi
else
    if ! grep -qP '^\s*password\s+'"$var_password_pam_remember_control_flag"'\s+pam_pwhistory.so\s*.*' "/etc/pam.d/password-auth"; then
        # Line matching group + control + module was not found. Check group + module.
        if [ "$(grep -cP '^\s*password\s+.*\s+pam_pwhistory.so\s*' "/etc/pam.d/password-auth")" -eq 1 ]; then
            # The control is updated only if one single line matches.
            sed -i -E --follow-symlinks 's/^(\s*password\s+).*(\bpam_pwhistory.so.*)/\1'"$var_password_pam_remember_control_flag"' \2/' "/etc/pam.d/password-auth"
        else
            LAST_MATCH_LINE=$(grep -nP "^password.*requisite.*pam_pwquality\.so" "/etc/pam.d/password-auth" | tail -n 1 | cut -d: -f 1)
            if [ ! -z $LAST_MATCH_LINE ]; then
                sed -i --follow-symlinks $LAST_MATCH_LINE' a password     '"$var_password_pam_remember_control_flag"'    pam_pwhistory.so' "/etc/pam.d/password-auth"
            else
                echo 'password    '"$var_password_pam_remember_control_flag"'    pam_pwhistory.so' >> "/etc/pam.d/password-auth"
            fi
        fi
    fi
fi

PWHISTORY_CONF="/etc/security/pwhistory.conf"
if [ -f $PWHISTORY_CONF ]; then
    regex="^\s*remember\s*="
    line="remember = $var_password_pam_remember"
    if ! grep -q $regex $PWHISTORY_CONF; then
        echo $line >> $PWHISTORY_CONF
    else
        sed -i --follow-symlinks 's|^\s*\(remember\s*=\s*\)\(\S\+\)|\1'"$var_password_pam_remember"'|g' $PWHISTORY_CONF
    fi
    if [ -e "/etc/pam.d/password-auth" ] ; then
        PAM_FILE_PATH="/etc/pam.d/password-auth"
        if [ -f /usr/bin/authselect ]; then
            
            if ! authselect check; then
            echo "
            authselect integrity check failed. Remediation aborted!
            This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
            It is not recommended to manually edit the PAM files when authselect tool is available.
            In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
            exit 1
            fi

            CURRENT_PROFILE=$(authselect current -r | awk '{ print $1 }')
            # If not already in use, a custom profile is created preserving the enabled features.
            if [[ ! $CURRENT_PROFILE == custom/* ]]; then
                ENABLED_FEATURES=$(authselect current | tail -n+3 | awk '{ print $2 }')
                authselect create-profile hardening -b $CURRENT_PROFILE
                CURRENT_PROFILE="custom/hardening"
                
                authselect apply-changes -b --backup=before-hardening-custom-profile
                authselect select $CURRENT_PROFILE
                for feature in $ENABLED_FEATURES; do
                    authselect enable-feature $feature;
                done
                
                authselect apply-changes -b --backup=after-hardening-custom-profile
            fi
            PAM_FILE_NAME=$(basename "/etc/pam.d/password-auth")
            PAM_FILE_PATH="/etc/authselect/$CURRENT_PROFILE/$PAM_FILE_NAME"

            authselect apply-changes -b
        fi
        
    if grep -qP '^\s*password\s.*\bpam_pwhistory.so\s.*\bremember\b' "$PAM_FILE_PATH"; then
        sed -i -E --follow-symlinks 's/(.*password.*pam_pwhistory.so.*)\bremember\b=?[[:alnum:]]*(.*)/\1\2/g' "$PAM_FILE_PATH"
    fi
        if [ -f /usr/bin/authselect ]; then
            
            authselect apply-changes -b
        fi
    else
        echo "/etc/pam.d/password-auth was not found" >&2
    fi
else
    PAM_FILE_PATH="/etc/pam.d/password-auth"
    if [ -f /usr/bin/authselect ]; then
        
        if ! authselect check; then
        echo "
        authselect integrity check failed. Remediation aborted!
        This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
        It is not recommended to manually edit the PAM files when authselect tool is available.
        In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
        exit 1
        fi

        CURRENT_PROFILE=$(authselect current -r | awk '{ print $1 }')
        # If not already in use, a custom profile is created preserving the enabled features.
        if [[ ! $CURRENT_PROFILE == custom/* ]]; then
            ENABLED_FEATURES=$(authselect current | tail -n+3 | awk '{ print $2 }')
            authselect create-profile hardening -b $CURRENT_PROFILE
            CURRENT_PROFILE="custom/hardening"
            
            authselect apply-changes -b --backup=before-hardening-custom-profile
            authselect select $CURRENT_PROFILE
            for feature in $ENABLED_FEATURES; do
                authselect enable-feature $feature;
            done
            
            authselect apply-changes -b --backup=after-hardening-custom-profile
        fi
        PAM_FILE_NAME=$(basename "/etc/pam.d/password-auth")
        PAM_FILE_PATH="/etc/authselect/$CURRENT_PROFILE/$PAM_FILE_NAME"

        authselect apply-changes -b
    fi
    if ! grep -qP '^\s*password\s+'"requisite"'\s+pam_pwhistory.so\s*.*' "$PAM_FILE_PATH"; then
        # Line matching group + control + module was not found. Check group + module.
        if [ "$(grep -cP '^\s*password\s+.*\s+pam_pwhistory.so\s*' "$PAM_FILE_PATH")" -eq 1 ]; then
            # The control is updated only if one single line matches.
            sed -i -E --follow-symlinks 's/^(\s*password\s+).*(\bpam_pwhistory.so.*)/\1'"requisite"' \2/' "$PAM_FILE_PATH"
        else
            echo 'password    '"requisite"'    pam_pwhistory.so' >> "$PAM_FILE_PATH"
        fi
    fi
    # Check the option
    if ! grep -qP '^\s*password\s+'"requisite"'\s+pam_pwhistory.so\s*.*\sremember\b' "$PAM_FILE_PATH"; then
        sed -i -E --follow-symlinks '/\s*password\s+'"requisite"'\s+pam_pwhistory.so.*/ s/$/ remember='"$var_password_pam_remember"'/' "$PAM_FILE_PATH"
    else
        sed -i -E --follow-symlinks 's/(\s*password\s+'"requisite"'\s+pam_pwhistory.so\s+.*)('"remember"'=)[[:alnum:]]+\s*(.*)/\1\2'"$var_password_pam_remember"' \3/' "$PAM_FILE_PATH"
    fi
    if [ -f /usr/bin/authselect ]; then
        
        authselect apply-changes -b
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Limit Password Reuse: system-auth   [ref]

Do not allow users to reuse recent passwords. This can be accomplished by using the remember option for the pam_pwhistory PAM module.

In the file /etc/pam.d/system-auth, make sure the parameter remember is present and it has a value equal to or greater than 5

For example: 
password requisite pam_pwhistory.so use_authtok remember=5
Warning:  If the system relies on authselect tool to manage PAM settings, the remediation will also use authselect tool. However, if any manual modification was made in PAM files, the authselect integrity check will fail and the remediation will be aborted in order to preserve intentional changes. In this case, an informative message will be shown in the remediation report.
Warning:  Newer versions of authselect contain an authselect feature to easily and properly enable pam_pwhistory.so module. If this feature is not yet available in your system, an authselect custom profile must be used to avoid integrity issues in PAM files.
Rationale:
Preventing re-use of previous passwords helps ensure that a compromised password is not re-used by a user.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_pwhistory_remember_system_auth
Identifiers and References

References:  BP28(R18), 1, 12, 15, 16, 5, 5.6.2.1.1, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10, 3.5.8, CCI-000200, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3, IA-5(f), IA-5(1)(e), PR.AC-1, PR.AC-6, PR.AC-7, Req-8.2.5, SRG-OS-000077-GPOS-00045, SRG-OS-000077-VMM-000440, 5.4.4, SV-204422r880836_rule


Complexity:low
Disruption:medium
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_system_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
- name: XCCDF Value var_password_pam_remember # promote to variable
  set_fact:
    var_password_pam_remember: !!str 5
  tags:
    - always
- name: XCCDF Value var_password_pam_remember_control_flag # promote to variable
  set_fact:
    var_password_pam_remember_control_flag: !!str requisite
  tags:
    - always

- name: 'Limit Password Reuse: system-auth - Check if system relies on authselect
    tool'
  ansible.builtin.stat:
    path: /usr/bin/authselect
  register: result_authselect_present
  when: '"pam" in ansible_facts.packages'
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_system_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed

- name: 'Limit Password Reuse: system-auth - Collect the available authselect features'
  ansible.builtin.command:
    cmd: authselect list-features minimal
  register: result_authselect_available_features
  changed_when: false
  when:
  - '"pam" in ansible_facts.packages'
  - result_authselect_present.stat.exists
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_system_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed

- name: 'Limit Password Reuse: system-auth - Enable pam_pwhistory.so using authselect
    feature'
  block:

  - name: 'Limit Password Reuse: system-auth - Check integrity of authselect current
      profile'
    ansible.builtin.command:
      cmd: authselect check
    register: result_authselect_check_cmd
    changed_when: false
    ignore_errors: true

  - name: 'Limit Password Reuse: system-auth - Informative message based on the authselect
      integrity check result'
    ansible.builtin.assert:
      that:
      - result_authselect_check_cmd is success
      fail_msg:
      - authselect integrity check failed. Remediation aborted!
      - This remediation could not be applied because an authselect profile was not
        selected or the selected profile is not intact.
      - It is not recommended to manually edit the PAM files when authselect tool
        is available.
      - In cases where the default authselect profile does not cover a specific demand,
        a custom authselect profile is recommended.
      success_msg:
      - authselect integrity check passed

  - name: 'Limit Password Reuse: system-auth - Get authselect current features'
    ansible.builtin.shell:
      cmd: authselect current | tail -n+3 | awk '{ print $2 }'
    register: result_authselect_features
    changed_when: false
    when:
    - result_authselect_check_cmd is success

  - name: 'Limit Password Reuse: system-auth - Ensure "with-pwhistory" feature is
      enabled using authselect tool'
    ansible.builtin.command:
      cmd: authselect enable-feature with-pwhistory
    register: result_authselect_enable_feature_cmd
    when:
    - result_authselect_check_cmd is success
    - result_authselect_features.stdout is not search("with-pwhistory")

  - name: 'Limit Password Reuse: system-auth - Ensure authselect changes are applied'
    ansible.builtin.command:
      cmd: authselect apply-changes -b
    when:
    - result_authselect_enable_feature_cmd is not skipped
    - result_authselect_enable_feature_cmd is success
  when:
  - '"pam" in ansible_facts.packages'
  - result_authselect_present.stat.exists
  - result_authselect_available_features.stdout is search("with-pwhistory")
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_system_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed

- name: 'Limit Password Reuse: system-auth - Enable pam_pwhistory.so in appropriate
    PAM files'
  block:

  - name: 'Limit Password Reuse: system-auth - Define the PAM file to be edited as
      a local fact'
    ansible.builtin.set_fact:
      pam_file_path: /etc/pam.d/system-auth

  - name: 'Limit Password Reuse: system-auth - Check if system relies on authselect
      tool'
    ansible.builtin.stat:
      path: /usr/bin/authselect
    register: result_authselect_present

  - name: 'Limit Password Reuse: system-auth - Ensure authselect custom profile is
      used if authselect is present'
    block:

    - name: 'Limit Password Reuse: system-auth - Check integrity of authselect current
        profile'
      ansible.builtin.command:
        cmd: authselect check
      register: result_authselect_check_cmd
      changed_when: false
      ignore_errors: true

    - name: 'Limit Password Reuse: system-auth - Informative message based on the
        authselect integrity check result'
      ansible.builtin.assert:
        that:
        - result_authselect_check_cmd is success
        fail_msg:
        - authselect integrity check failed. Remediation aborted!
        - This remediation could not be applied because an authselect profile was
          not selected or the selected profile is not intact.
        - It is not recommended to manually edit the PAM files when authselect tool
          is available.
        - In cases where the default authselect profile does not cover a specific
          demand, a custom authselect profile is recommended.
        success_msg:
        - authselect integrity check passed

    - name: 'Limit Password Reuse: system-auth - Get authselect current profile'
      ansible.builtin.shell:
        cmd: authselect current -r | awk '{ print $1 }'
      register: result_authselect_profile
      changed_when: false
      when:
      - result_authselect_check_cmd is success

    - name: 'Limit Password Reuse: system-auth - Define the current authselect profile
        as a local fact'
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: '{{ result_authselect_profile.stdout }}'
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is match("custom/")

    - name: 'Limit Password Reuse: system-auth - Define the new authselect custom
        profile as a local fact'
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: custom/hardening
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is not match("custom/")

    - name: 'Limit Password Reuse: system-auth - Get authselect current features to
        also enable them in the custom profile'
      ansible.builtin.shell:
        cmd: authselect current | tail -n+3 | awk '{ print $2 }'
      register: result_authselect_features
      changed_when: false
      when:
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")

    - name: 'Limit Password Reuse: system-auth - Check if any custom profile with
        the same name was already created'
      ansible.builtin.stat:
        path: /etc/authselect/{{ authselect_custom_profile }}
      register: result_authselect_custom_profile_present
      changed_when: false
      when:
      - authselect_current_profile is not match("custom/")

    - name: 'Limit Password Reuse: system-auth - Create an authselect custom profile
        based on the current profile'
      ansible.builtin.command:
        cmd: authselect create-profile hardening -b {{ authselect_current_profile
          }}
      when:
      - result_authselect_check_cmd is success
      - authselect_current_profile is not match("custom/")
      - not result_authselect_custom_profile_present.stat.exists

    - name: 'Limit Password Reuse: system-auth - Ensure authselect changes are applied'
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=before-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: 'Limit Password Reuse: system-auth - Ensure the authselect custom profile
        is selected'
      ansible.builtin.command:
        cmd: authselect select {{ authselect_custom_profile }}
      register: result_pam_authselect_select_profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: 'Limit Password Reuse: system-auth - Restore the authselect features in
        the custom profile'
      ansible.builtin.command:
        cmd: authselect enable-feature {{ item }}
      loop: '{{ result_authselect_features.stdout_lines }}'
      register: result_pam_authselect_restore_features
      when:
      - result_authselect_profile is not skipped
      - result_authselect_features is not skipped
      - result_pam_authselect_select_profile is not skipped

    - name: 'Limit Password Reuse: system-auth - Ensure authselect changes are applied'
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=after-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - result_pam_authselect_restore_features is not skipped

    - name: 'Limit Password Reuse: system-auth - Change the PAM file to be edited
        according to the custom authselect profile'
      ansible.builtin.set_fact:
        pam_file_path: /etc/authselect/{{ authselect_custom_profile }}/{{ pam_file_path
          | basename }}
    when:
    - result_authselect_present.stat.exists

  - name: 'Limit Password Reuse: system-auth - Check if expected PAM module line is
      present in {{ pam_file_path }}'
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      regexp: ^\s*password\s+{{ var_password_pam_remember_control_flag.split(",")[0]
        }}\s+pam_pwhistory.so\s*.*
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_line_present

  - name: 'Limit Password Reuse: system-auth - Include or update the PAM module line
      in {{ pam_file_path }}'
    block:

    - name: 'Limit Password Reuse: system-auth - Check if required PAM module line
        is present in {{ pam_file_path }} with different control'
      ansible.builtin.lineinfile:
        path: '{{ pam_file_path }}'
        regexp: ^\s*password\s+.*\s+pam_pwhistory.so\s*
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_line_other_control_present

    - name: 'Limit Password Reuse: system-auth - Ensure the correct control for the
        required PAM module line in {{ pam_file_path }}'
      ansible.builtin.replace:
        dest: '{{ pam_file_path }}'
        regexp: ^(\s*password\s+).*(\bpam_pwhistory.so.*)
        replace: \1{{ var_password_pam_remember_control_flag.split(",")[0] }} \2
      register: result_pam_module_edit
      when:
      - result_pam_line_other_control_present.found == 1

    - name: 'Limit Password Reuse: system-auth - Ensure the required PAM module line
        is included in {{ pam_file_path }}'
      ansible.builtin.lineinfile:
        dest: '{{ pam_file_path }}'
        insertafter: ^password.*requisite.*pam_pwquality\.so
        line: password    {{ var_password_pam_remember_control_flag.split(",")[0]
          }}    pam_pwhistory.so
      register: result_pam_module_add
      when:
      - result_pam_line_other_control_present.found == 0 or result_pam_line_other_control_present.found
        > 1

    - name: 'Limit Password Reuse: system-auth - Ensure authselect changes are applied'
      ansible.builtin.command:
        cmd: authselect apply-changes -b
      when: |
        result_authselect_present is defined and result_authselect_present.stat.exists and ((result_pam_module_add is defined and result_pam_module_add.changed) or (result_pam_module_edit is defined and result_pam_module_edit.changed))
    when:
    - result_pam_line_present.found is defined
    - result_pam_line_present.found == 0
  when:
  - '"pam" in ansible_facts.packages'
  - |
    (result_authselect_available_features.stdout is defined and result_authselect_available_features.stdout is not search("with-pwhistory")) or result_authselect_available_features is not defined
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_system_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed

- name: 'Limit Password Reuse: system-auth - Check the presence of /etc/security/pwhistory.conf
    file'
  ansible.builtin.stat:
    path: /etc/security/pwhistory.conf
  register: result_pwhistory_conf_check
  when: '"pam" in ansible_facts.packages'
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_system_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed

- name: 'Limit Password Reuse: system-auth - pam_pwhistory.so parameters are configured
    in /etc/security/pwhistory.conf file'
  block:

  - name: 'Limit Password Reuse: system-auth - Ensure the pam_pwhistory.so remember
      parameter in /etc/security/pwhistory.conf'
    ansible.builtin.lineinfile:
      path: /etc/security/pwhistory.conf
      regexp: ^\s*remember\s*=
      line: remember = {{ var_password_pam_remember }}
      state: present

  - name: 'Limit Password Reuse: system-auth - Ensure the pam_pwhistory.so remember
      parameter is removed from PAM files'
    block:

    - name: 'Limit Password Reuse: system-auth - Check if /etc/pam.d/system-auth file
        is present'
      ansible.builtin.stat:
        path: /etc/pam.d/system-auth
      register: result_pam_file_present

    - name: 'Limit Password Reuse: system-auth - Check the proper remediation for
        the system'
      block:

      - name: 'Limit Password Reuse: system-auth - Define the PAM file to be edited
          as a local fact'
        ansible.builtin.set_fact:
          pam_file_path: /etc/pam.d/system-auth

      - name: 'Limit Password Reuse: system-auth - Check if system relies on authselect
          tool'
        ansible.builtin.stat:
          path: /usr/bin/authselect
        register: result_authselect_present

      - name: 'Limit Password Reuse: system-auth - Ensure authselect custom profile
          is used if authselect is present'
        block:

        - name: 'Limit Password Reuse: system-auth - Check integrity of authselect
            current profile'
          ansible.builtin.command:
            cmd: authselect check
          register: result_authselect_check_cmd
          changed_when: false
          ignore_errors: true

        - name: 'Limit Password Reuse: system-auth - Informative message based on
            the authselect integrity check result'
          ansible.builtin.assert:
            that:
            - result_authselect_check_cmd is success
            fail_msg:
            - authselect integrity check failed. Remediation aborted!
            - This remediation could not be applied because an authselect profile
              was not selected or the selected profile is not intact.
            - It is not recommended to manually edit the PAM files when authselect
              tool is available.
            - In cases where the default authselect profile does not cover a specific
              demand, a custom authselect profile is recommended.
            success_msg:
            - authselect integrity check passed

        - name: 'Limit Password Reuse: system-auth - Get authselect current profile'
          ansible.builtin.shell:
            cmd: authselect current -r | awk '{ print $1 }'
          register: result_authselect_profile
          changed_when: false
          when:
          - result_authselect_check_cmd is success

        - name: 'Limit Password Reuse: system-auth - Define the current authselect
            profile as a local fact'
          ansible.builtin.set_fact:
            authselect_current_profile: '{{ result_authselect_profile.stdout }}'
            authselect_custom_profile: '{{ result_authselect_profile.stdout }}'
          when:
          - result_authselect_profile is not skipped
          - result_authselect_profile.stdout is match("custom/")

        - name: 'Limit Password Reuse: system-auth - Define the new authselect custom
            profile as a local fact'
          ansible.builtin.set_fact:
            authselect_current_profile: '{{ result_authselect_profile.stdout }}'
            authselect_custom_profile: custom/hardening
          when:
          - result_authselect_profile is not skipped
          - result_authselect_profile.stdout is not match("custom/")

        - name: 'Limit Password Reuse: system-auth - Get authselect current features
            to also enable them in the custom profile'
          ansible.builtin.shell:
            cmd: authselect current | tail -n+3 | awk '{ print $2 }'
          register: result_authselect_features
          changed_when: false
          when:
          - result_authselect_profile is not skipped
          - authselect_current_profile is not match("custom/")

        - name: 'Limit Password Reuse: system-auth - Check if any custom profile with
            the same name was already created'
          ansible.builtin.stat:
            path: /etc/authselect/{{ authselect_custom_profile }}
          register: result_authselect_custom_profile_present
          changed_when: false
          when:
          - authselect_current_profile is not match("custom/")

        - name: 'Limit Password Reuse: system-auth - Create an authselect custom profile
            based on the current profile'
          ansible.builtin.command:
            cmd: authselect create-profile hardening -b {{ authselect_current_profile
              }}
          when:
          - result_authselect_check_cmd is success
          - authselect_current_profile is not match("custom/")
          - not result_authselect_custom_profile_present.stat.exists

        - name: 'Limit Password Reuse: system-auth - Ensure authselect changes are
            applied'
          ansible.builtin.command:
            cmd: authselect apply-changes -b --backup=before-hardening-custom-profile
          when:
          - result_authselect_check_cmd is success
          - result_authselect_profile is not skipped
          - authselect_current_profile is not match("custom/")
          - authselect_custom_profile is not match(authselect_current_profile)

        - name: 'Limit Password Reuse: system-auth - Ensure the authselect custom
            profile is selected'
          ansible.builtin.command:
            cmd: authselect select {{ authselect_custom_profile }}
          register: result_pam_authselect_select_profile
          when:
          - result_authselect_check_cmd is success
          - result_authselect_profile is not skipped
          - authselect_current_profile is not match("custom/")
          - authselect_custom_profile is not match(authselect_current_profile)

        - name: 'Limit Password Reuse: system-auth - Restore the authselect features
            in the custom profile'
          ansible.builtin.command:
            cmd: authselect enable-feature {{ item }}
          loop: '{{ result_authselect_features.stdout_lines }}'
          register: result_pam_authselect_restore_features
          when:
          - result_authselect_profile is not skipped
          - result_authselect_features is not skipped
          - result_pam_authselect_select_profile is not skipped

        - name: 'Limit Password Reuse: system-auth - Ensure authselect changes are
            applied'
          ansible.builtin.command:
            cmd: authselect apply-changes -b --backup=after-hardening-custom-profile
          when:
          - result_authselect_check_cmd is success
          - result_authselect_profile is not skipped
          - result_pam_authselect_restore_features is not skipped

        - name: 'Limit Password Reuse: system-auth - Change the PAM file to be edited
            according to the custom authselect profile'
          ansible.builtin.set_fact:
            pam_file_path: /etc/authselect/{{ authselect_custom_profile }}/{{ pam_file_path
              | basename }}
        when:
        - result_authselect_present.stat.exists

      - name: 'Limit Password Reuse: system-auth - Ensure the "remember" option from
          "pam_pwhistory.so" is not present in {{ pam_file_path }}'
        ansible.builtin.replace:
          dest: '{{ pam_file_path }}'
          regexp: (.*password.*pam_pwhistory.so.*)\bremember\b=?[0-9a-zA-Z]*(.*)
          replace: \1\2
        register: result_pam_option_removal

      - name: 'Limit Password Reuse: system-auth - Ensure authselect changes are applied'
        ansible.builtin.command:
          cmd: authselect apply-changes -b
        when:
        - result_authselect_present.stat.exists
        - result_pam_option_removal is changed
      when:
      - result_pam_file_present.stat.exists
  when:
  - '"pam" in ansible_facts.packages'
  - result_pwhistory_conf_check.stat.exists
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_system_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed

- name: 'Limit Password Reuse: system-auth - pam_pwhistory.so parameters are configured
    in PAM files'
  block:

  - name: 'Limit Password Reuse: system-auth - Define the PAM file to be edited as
      a local fact'
    ansible.builtin.set_fact:
      pam_file_path: /etc/pam.d/system-auth

  - name: 'Limit Password Reuse: system-auth - Check if system relies on authselect
      tool'
    ansible.builtin.stat:
      path: /usr/bin/authselect
    register: result_authselect_present

  - name: 'Limit Password Reuse: system-auth - Ensure authselect custom profile is
      used if authselect is present'
    block:

    - name: 'Limit Password Reuse: system-auth - Check integrity of authselect current
        profile'
      ansible.builtin.command:
        cmd: authselect check
      register: result_authselect_check_cmd
      changed_when: false
      ignore_errors: true

    - name: 'Limit Password Reuse: system-auth - Informative message based on the
        authselect integrity check result'
      ansible.builtin.assert:
        that:
        - result_authselect_check_cmd is success
        fail_msg:
        - authselect integrity check failed. Remediation aborted!
        - This remediation could not be applied because an authselect profile was
          not selected or the selected profile is not intact.
        - It is not recommended to manually edit the PAM files when authselect tool
          is available.
        - In cases where the default authselect profile does not cover a specific
          demand, a custom authselect profile is recommended.
        success_msg:
        - authselect integrity check passed

    - name: 'Limit Password Reuse: system-auth - Get authselect current profile'
      ansible.builtin.shell:
        cmd: authselect current -r | awk '{ print $1 }'
      register: result_authselect_profile
      changed_when: false
      when:
      - result_authselect_check_cmd is success

    - name: 'Limit Password Reuse: system-auth - Define the current authselect profile
        as a local fact'
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: '{{ result_authselect_profile.stdout }}'
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is match("custom/")

    - name: 'Limit Password Reuse: system-auth - Define the new authselect custom
        profile as a local fact'
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: custom/hardening
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is not match("custom/")

    - name: 'Limit Password Reuse: system-auth - Get authselect current features to
        also enable them in the custom profile'
      ansible.builtin.shell:
        cmd: authselect current | tail -n+3 | awk '{ print $2 }'
      register: result_authselect_features
      changed_when: false
      when:
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")

    - name: 'Limit Password Reuse: system-auth - Check if any custom profile with
        the same name was already created'
      ansible.builtin.stat:
        path: /etc/authselect/{{ authselect_custom_profile }}
      register: result_authselect_custom_profile_present
      changed_when: false
      when:
      - authselect_current_profile is not match("custom/")

    - name: 'Limit Password Reuse: system-auth - Create an authselect custom profile
        based on the current profile'
      ansible.builtin.command:
        cmd: authselect create-profile hardening -b {{ authselect_current_profile
          }}
      when:
      - result_authselect_check_cmd is success
      - authselect_current_profile is not match("custom/")
      - not result_authselect_custom_profile_present.stat.exists

    - name: 'Limit Password Reuse: system-auth - Ensure authselect changes are applied'
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=before-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: 'Limit Password Reuse: system-auth - Ensure the authselect custom profile
        is selected'
      ansible.builtin.command:
        cmd: authselect select {{ authselect_custom_profile }}
      register: result_pam_authselect_select_profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: 'Limit Password Reuse: system-auth - Restore the authselect features in
        the custom profile'
      ansible.builtin.command:
        cmd: authselect enable-feature {{ item }}
      loop: '{{ result_authselect_features.stdout_lines }}'
      register: result_pam_authselect_restore_features
      when:
      - result_authselect_profile is not skipped
      - result_authselect_features is not skipped
      - result_pam_authselect_select_profile is not skipped

    - name: 'Limit Password Reuse: system-auth - Ensure authselect changes are applied'
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=after-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - result_pam_authselect_restore_features is not skipped

    - name: 'Limit Password Reuse: system-auth - Change the PAM file to be edited
        according to the custom authselect profile'
      ansible.builtin.set_fact:
        pam_file_path: /etc/authselect/{{ authselect_custom_profile }}/{{ pam_file_path
          | basename }}
    when:
    - result_authselect_present.stat.exists

  - name: 'Limit Password Reuse: system-auth - Check if expected PAM module line is
      present in {{ pam_file_path }}'
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      regexp: ^\s*password\s+requisite\s+pam_pwhistory.so\s*.*
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_line_present

  - name: 'Limit Password Reuse: system-auth - Include or update the PAM module line
      in {{ pam_file_path }}'
    block:

    - name: 'Limit Password Reuse: system-auth - Check if required PAM module line
        is present in {{ pam_file_path }} with different control'
      ansible.builtin.lineinfile:
        path: '{{ pam_file_path }}'
        regexp: ^\s*password\s+.*\s+pam_pwhistory.so\s*
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_line_other_control_present

    - name: 'Limit Password Reuse: system-auth - Ensure the correct control for the
        required PAM module line in {{ pam_file_path }}'
      ansible.builtin.replace:
        dest: '{{ pam_file_path }}'
        regexp: ^(\s*password\s+).*(\bpam_pwhistory.so.*)
        replace: \1requisite \2
      register: result_pam_module_edit
      when:
      - result_pam_line_other_control_present.found == 1

    - name: 'Limit Password Reuse: system-auth - Ensure the required PAM module line
        is included in {{ pam_file_path }}'
      ansible.builtin.lineinfile:
        dest: '{{ pam_file_path }}'
        line: password    requisite    pam_pwhistory.so
      register: result_pam_module_add
      when:
      - result_pam_line_other_control_present.found == 0 or result_pam_line_other_control_present.found
        > 1

    - name: 'Limit Password Reuse: system-auth - Ensure authselect changes are applied'
      ansible.builtin.command:
        cmd: authselect apply-changes -b
      when: |
        result_authselect_present is defined and result_authselect_present.stat.exists and ((result_pam_module_add is defined and result_pam_module_add.changed) or (result_pam_module_edit is defined and result_pam_module_edit.changed))
    when:
    - result_pam_line_present.found is defined
    - result_pam_line_present.found == 0

  - name: 'Limit Password Reuse: system-auth - Check if the required PAM module option
      is present in {{ pam_file_path }}'
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      regexp: ^\s*password\s+requisite\s+pam_pwhistory.so\s*.*\sremember\b
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_module_remember_option_present

  - name: 'Limit Password Reuse: system-auth - Ensure the "remember" PAM option for
      "pam_pwhistory.so" is included in {{ pam_file_path }}'
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      backrefs: true
      regexp: ^(\s*password\s+requisite\s+pam_pwhistory.so.*)
      line: \1 remember={{ var_password_pam_remember }}
      state: present
    register: result_pam_remember_add
    when:
    - result_pam_module_remember_option_present.found == 0

  - name: 'Limit Password Reuse: system-auth - Ensure the required value for "remember"
      PAM option from "pam_pwhistory.so" in {{ pam_file_path }}'
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      backrefs: true
      regexp: ^(\s*password\s+requisite\s+pam_pwhistory.so\s+.*)(remember)=[0-9a-zA-Z]+\s*(.*)
      line: \1\2={{ var_password_pam_remember }} \3
    register: result_pam_remember_edit
    when:
    - result_pam_module_remember_option_present.found > 0

  - name: 'Limit Password Reuse: system-auth - Ensure authselect changes are applied'
    ansible.builtin.command:
      cmd: authselect apply-changes -b
    when:
    - result_authselect_present.stat.exists
    - (result_pam_remember_add is defined and result_pam_remember_add.changed) or
      (result_pam_remember_edit is defined and result_pam_remember_edit.changed)
  when:
  - '"pam" in ansible_facts.packages'
  - not result_pwhistory_conf_check.stat.exists
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010270
  - NIST-800-171-3.5.8
  - NIST-800-53-IA-5(1)(e)
  - NIST-800-53-IA-5(f)
  - PCI-DSS-Req-8.2.5
  - accounts_password_pam_pwhistory_remember_system_auth
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed


# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_password_pam_remember='5'
var_password_pam_remember_control_flag='requisite'


var_password_pam_remember_control_flag="$(echo $var_password_pam_remember_control_flag | cut -d \, -f 1)"

if [ -f /usr/bin/authselect ]; then
    if authselect list-features minimal | grep -q with-pwhistory; then
        if ! authselect check; then
        echo "
        authselect integrity check failed. Remediation aborted!
        This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
        It is not recommended to manually edit the PAM files when authselect tool is available.
        In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
        exit 1
        fi
        authselect enable-feature with-pwhistory

        authselect apply-changes -b
    else
        
        if ! authselect check; then
        echo "
        authselect integrity check failed. Remediation aborted!
        This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
        It is not recommended to manually edit the PAM files when authselect tool is available.
        In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
        exit 1
        fi

        CURRENT_PROFILE=$(authselect current -r | awk '{ print $1 }')
        # If not already in use, a custom profile is created preserving the enabled features.
        if [[ ! $CURRENT_PROFILE == custom/* ]]; then
            ENABLED_FEATURES=$(authselect current | tail -n+3 | awk '{ print $2 }')
            authselect create-profile hardening -b $CURRENT_PROFILE
            CURRENT_PROFILE="custom/hardening"
            
            authselect apply-changes -b --backup=before-hardening-custom-profile
            authselect select $CURRENT_PROFILE
            for feature in $ENABLED_FEATURES; do
                authselect enable-feature $feature;
            done
            
            authselect apply-changes -b --backup=after-hardening-custom-profile
        fi
        PAM_FILE_NAME=$(basename "/etc/pam.d/system-auth")
        PAM_FILE_PATH="/etc/authselect/$CURRENT_PROFILE/$PAM_FILE_NAME"

        authselect apply-changes -b
        if ! grep -qP '^\s*password\s+'"$var_password_pam_remember_control_flag"'\s+pam_pwhistory.so\s*.*' "$PAM_FILE_PATH"; then
            # Line matching group + control + module was not found. Check group + module.
            if [ "$(grep -cP '^\s*password\s+.*\s+pam_pwhistory.so\s*' "$PAM_FILE_PATH")" -eq 1 ]; then
                # The control is updated only if one single line matches.
                sed -i -E --follow-symlinks 's/^(\s*password\s+).*(\bpam_pwhistory.so.*)/\1'"$var_password_pam_remember_control_flag"' \2/' "$PAM_FILE_PATH"
            else
                LAST_MATCH_LINE=$(grep -nP "^password.*requisite.*pam_pwquality\.so" "$PAM_FILE_PATH" | tail -n 1 | cut -d: -f 1)
                if [ ! -z $LAST_MATCH_LINE ]; then
                    sed -i --follow-symlinks $LAST_MATCH_LINE' a password     '"$var_password_pam_remember_control_flag"'    pam_pwhistory.so' "$PAM_FILE_PATH"
                else
                    echo 'password    '"$var_password_pam_remember_control_flag"'    pam_pwhistory.so' >> "$PAM_FILE_PATH"
                fi
            fi
        fi
    fi
else
    if ! grep -qP '^\s*password\s+'"$var_password_pam_remember_control_flag"'\s+pam_pwhistory.so\s*.*' "/etc/pam.d/system-auth"; then
        # Line matching group + control + module was not found. Check group + module.
        if [ "$(grep -cP '^\s*password\s+.*\s+pam_pwhistory.so\s*' "/etc/pam.d/system-auth")" -eq 1 ]; then
            # The control is updated only if one single line matches.
            sed -i -E --follow-symlinks 's/^(\s*password\s+).*(\bpam_pwhistory.so.*)/\1'"$var_password_pam_remember_control_flag"' \2/' "/etc/pam.d/system-auth"
        else
            LAST_MATCH_LINE=$(grep -nP "^password.*requisite.*pam_pwquality\.so" "/etc/pam.d/system-auth" | tail -n 1 | cut -d: -f 1)
            if [ ! -z $LAST_MATCH_LINE ]; then
                sed -i --follow-symlinks $LAST_MATCH_LINE' a password     '"$var_password_pam_remember_control_flag"'    pam_pwhistory.so' "/etc/pam.d/system-auth"
            else
                echo 'password    '"$var_password_pam_remember_control_flag"'    pam_pwhistory.so' >> "/etc/pam.d/system-auth"
            fi
        fi
    fi
fi

PWHISTORY_CONF="/etc/security/pwhistory.conf"
if [ -f $PWHISTORY_CONF ]; then
    regex="^\s*remember\s*="
    line="remember = $var_password_pam_remember"
    if ! grep -q $regex $PWHISTORY_CONF; then
        echo $line >> $PWHISTORY_CONF
    else
        sed -i --follow-symlinks 's|^\s*\(remember\s*=\s*\)\(\S\+\)|\1'"$var_password_pam_remember"'|g' $PWHISTORY_CONF
    fi
    if [ -e "/etc/pam.d/system-auth" ] ; then
        PAM_FILE_PATH="/etc/pam.d/system-auth"
        if [ -f /usr/bin/authselect ]; then
            
            if ! authselect check; then
            echo "
            authselect integrity check failed. Remediation aborted!
            This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
            It is not recommended to manually edit the PAM files when authselect tool is available.
            In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
            exit 1
            fi

            CURRENT_PROFILE=$(authselect current -r | awk '{ print $1 }')
            # If not already in use, a custom profile is created preserving the enabled features.
            if [[ ! $CURRENT_PROFILE == custom/* ]]; then
                ENABLED_FEATURES=$(authselect current | tail -n+3 | awk '{ print $2 }')
                authselect create-profile hardening -b $CURRENT_PROFILE
                CURRENT_PROFILE="custom/hardening"
                
                authselect apply-changes -b --backup=before-hardening-custom-profile
                authselect select $CURRENT_PROFILE
                for feature in $ENABLED_FEATURES; do
                    authselect enable-feature $feature;
                done
                
                authselect apply-changes -b --backup=after-hardening-custom-profile
            fi
            PAM_FILE_NAME=$(basename "/etc/pam.d/system-auth")
            PAM_FILE_PATH="/etc/authselect/$CURRENT_PROFILE/$PAM_FILE_NAME"

            authselect apply-changes -b
        fi
        
    if grep -qP '^\s*password\s.*\bpam_pwhistory.so\s.*\bremember\b' "$PAM_FILE_PATH"; then
        sed -i -E --follow-symlinks 's/(.*password.*pam_pwhistory.so.*)\bremember\b=?[[:alnum:]]*(.*)/\1\2/g' "$PAM_FILE_PATH"
    fi
        if [ -f /usr/bin/authselect ]; then
            
            authselect apply-changes -b
        fi
    else
        echo "/etc/pam.d/system-auth was not found" >&2
    fi
else
    PAM_FILE_PATH="/etc/pam.d/system-auth"
    if [ -f /usr/bin/authselect ]; then
        
        if ! authselect check; then
        echo "
        authselect integrity check failed. Remediation aborted!
        This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
        It is not recommended to manually edit the PAM files when authselect tool is available.
        In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
        exit 1
        fi

        CURRENT_PROFILE=$(authselect current -r | awk '{ print $1 }')
        # If not already in use, a custom profile is created preserving the enabled features.
        if [[ ! $CURRENT_PROFILE == custom/* ]]; then
            ENABLED_FEATURES=$(authselect current | tail -n+3 | awk '{ print $2 }')
            authselect create-profile hardening -b $CURRENT_PROFILE
            CURRENT_PROFILE="custom/hardening"
            
            authselect apply-changes -b --backup=before-hardening-custom-profile
            authselect select $CURRENT_PROFILE
            for feature in $ENABLED_FEATURES; do
                authselect enable-feature $feature;
            done
            
            authselect apply-changes -b --backup=after-hardening-custom-profile
        fi
        PAM_FILE_NAME=$(basename "/etc/pam.d/system-auth")
        PAM_FILE_PATH="/etc/authselect/$CURRENT_PROFILE/$PAM_FILE_NAME"

        authselect apply-changes -b
    fi
    if ! grep -qP '^\s*password\s+'"requisite"'\s+pam_pwhistory.so\s*.*' "$PAM_FILE_PATH"; then
        # Line matching group + control + module was not found. Check group + module.
        if [ "$(grep -cP '^\s*password\s+.*\s+pam_pwhistory.so\s*' "$PAM_FILE_PATH")" -eq 1 ]; then
            # The control is updated only if one single line matches.
            sed -i -E --follow-symlinks 's/^(\s*password\s+).*(\bpam_pwhistory.so.*)/\1'"requisite"' \2/' "$PAM_FILE_PATH"
        else
            echo 'password    '"requisite"'    pam_pwhistory.so' >> "$PAM_FILE_PATH"
        fi
    fi
    # Check the option
    if ! grep -qP '^\s*password\s+'"requisite"'\s+pam_pwhistory.so\s*.*\sremember\b' "$PAM_FILE_PATH"; then
        sed -i -E --follow-symlinks '/\s*password\s+'"requisite"'\s+pam_pwhistory.so.*/ s/$/ remember='"$var_password_pam_remember"'/' "$PAM_FILE_PATH"
    else
        sed -i -E --follow-symlinks 's/(\s*password\s+'"requisite"'\s+pam_pwhistory.so\s+.*)('"remember"'=)[[:alnum:]]+\s*(.*)/\1\2'"$var_password_pam_remember"' \3/' "$PAM_FILE_PATH"
    fi
    if [ -f /usr/bin/authselect ]; then
        
        authselect apply-changes -b
    fi
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Set Password Quality Requirements   Group contains 1 group and 2 rules
[ref]   The default pam_pwquality PAM module provides strength checking for passwords. It performs a number of checks, such as making sure passwords are not similar to dictionary words, are of at least a certain length, are not the previous password reversed, and are not simply a change of case from the previous password. It can also require passwords to be in certain character classes. The pam_pwquality module is the preferred way of configuring password requirements.

The man pages pam_pwquality(8) provide information on the capabilities and configuration of each.
Group   Set Password Quality Requirements with pam_pwquality   Group contains 2 rules
[ref]   The pam_pwquality PAM module can be configured to meet requirements for a variety of policies.

For example, to configure pam_pwquality to require at least one uppercase character, lowercase character, digit, and other (special) character, make sure that pam_pwquality exists in /etc/pam.d/system-auth: 
password    requisite     pam_pwquality.so try_first_pass local_users_only retry=3 authtok_type=
If no such line exists, add one as the first line of the password section in /etc/pam.d/system-auth. Next, modify the settings in /etc/security/pwquality.conf to match the following: 
difok = 4
minlen = 14
dcredit = -1
ucredit = -1
lcredit = -1
ocredit = -1
maxrepeat = 3
The arguments can be modified to ensure compliance with your organization's security policy. Discussion of each parameter follows.

Rule   Ensure PAM Enforces Password Requirements - Minimum Different Categories   [ref]

The pam_pwquality module's minclass parameter controls requirements for usage of different character classes, or types, of character that must exist in a password before it is considered valid. For example, setting this value to three (3) requires that any password must have characters from at least three different categories in order to be approved. The default value is zero (0), meaning there are no required classes. There are four categories available: 
* Upper-case characters
* Lower-case characters
* Digits
* Special characters (for example, punctuation)
Modify the minclass setting in /etc/security/pwquality.conf entry to require 4 differing categories of characters when changing passwords.
Rationale:
Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.

Requiring a minimum number of character categories makes password guessing attacks more difficult by ensuring a larger search space.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_minclass
Identifiers and References

References:  1, 12, 15, 16, 5, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10, CCI-000195, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3, IA-5(c), IA-5(1)(a), CM-6(a), IA-5(4), PR.AC-1, PR.AC-6, PR.AC-7, SRG-OS-000072-GPOS-00040, 5.4.1, SV-204412r603261_rule


Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - DISA-STIG-RHEL-07-010170
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(a)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - accounts_password_pam_minclass
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_password_pam_minclass # promote to variable
  set_fact:
    var_password_pam_minclass: !!str 4
  tags:
    - always

- name: Ensure PAM Enforces Password Requirements - Minimum Different Categories -
    Ensure PAM variable minclass is set accordingly
  ansible.builtin.lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*minclass
    line: minclass = {{ var_password_pam_minclass }}
  when: '"pam" in ansible_facts.packages'
  tags:
  - DISA-STIG-RHEL-07-010170
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(a)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - accounts_password_pam_minclass
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Complexity:low
Disruption:low
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_password_pam_minclass='4'






# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/security/pwquality.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^minclass")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$var_password_pam_minclass"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^minclass\\>" "/etc/security/pwquality.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    "${sed_command[@]}" "s/^minclass\\>.*/$escaped_formatted_output/gi" "/etc/security/pwquality.conf"
else
    # \n is precaution for case where file ends without trailing newline
    cce=""
    printf '\n# Per %s: Set %s in %s\n' "$cce" "$formatted_output" "/etc/security/pwquality.conf" >> "/etc/security/pwquality.conf"
    printf '%s\n' "$formatted_output" >> "/etc/security/pwquality.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure PAM Enforces Password Requirements - Minimum Length   [ref]

The pam_pwquality module's minlen parameter controls requirements for minimum characters required in a password. Add minlen=14 after pam_pwquality to set minimum password length requirements.
Rationale:
The shorter the password, the lower the number of possible combinations that need to be tested before the password is compromised.
Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password length is one factor of several that helps to determine strength and how long it takes to crack a password. Use of more characters in a password helps to exponentially increase the time and/or resources required to compromise the password.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_pam_minlen
Identifiers and References

References:  BP28(R18), 1, 12, 15, 16, 5, 5.6.2.1.1, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10, CCI-000205, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3, IA-5(c), IA-5(1)(a), CM-6(a), IA-5(4), PR.AC-1, PR.AC-6, PR.AC-7, FMT_SMF_EXT.1, Req-8.2.3, SRG-OS-000078-GPOS-00046, SRG-OS-000072-VMM-000390, SRG-OS-000078-VMM-000450, 5.4.1, SV-204423r603261_rule


Complexity:low
Disruption:low
Strategy:restrict
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010280
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(a)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.3
  - accounts_password_pam_minlen
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
- name: XCCDF Value var_password_pam_minlen # promote to variable
  set_fact:
    var_password_pam_minlen: !!str 14
  tags:
    - always

- name: Ensure PAM Enforces Password Requirements - Minimum Length - Ensure PAM variable
    minlen is set accordingly
  ansible.builtin.lineinfile:
    create: true
    dest: /etc/security/pwquality.conf
    regexp: ^#?\s*minlen
    line: minlen = {{ var_password_pam_minlen }}
  when: '"pam" in ansible_facts.packages'
  tags:
  - CJIS-5.6.2.1.1
  - DISA-STIG-RHEL-07-010280
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(a)
  - NIST-800-53-IA-5(4)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.3
  - accounts_password_pam_minlen
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Complexity:low
Disruption:low
Strategy:restrict
# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_password_pam_minlen='14'






# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/security/pwquality.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^minlen")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$var_password_pam_minlen"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^minlen\\>" "/etc/security/pwquality.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    "${sed_command[@]}" "s/^minlen\\>.*/$escaped_formatted_output/gi" "/etc/security/pwquality.conf"
else
    # \n is precaution for case where file ends without trailing newline
    cce=""
    printf '\n# Per %s: Set %s in %s\n' "$cce" "$formatted_output" "/etc/security/pwquality.conf" >> "/etc/security/pwquality.conf"
    printf '%s\n' "$formatted_output" >> "/etc/security/pwquality.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Set Password Hashing Algorithm   Group contains 1 rule
[ref]   The system's default algorithm for storing password hashes in /etc/shadow is SHA-512. This can be configured in several locations.

Rule   Set PAM''s Password Hashing Algorithm   [ref]

The PAM system service can be configured to only store encrypted representations of passwords. In "/etc/pam.d/system-auth", the password section of the file controls which PAM modules execute during a password change. Set the pam_unix.so module in the password section to include the argument sha512, as shown below: 
password    sufficient    pam_unix.so sha512 other arguments...

This will help ensure when local users change their passwords, hashes for the new passwords will be generated using the SHA-512 algorithm. This is the default.
Rationale:
Passwords need to be protected at all times, and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily compromised. Passwords that are encrypted with a weak algorithm are no more protected than if they are kepy in plain text.

This setting ensures user and group account administration utilities are configured to store only encrypted representations of passwords. Additionally, the crypt_style configuration option ensures the use of a strong hashing algorithm that makes password cracking attacks more difficult.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_password_hashing_algorithm_systemauth
Identifiers and References

References:  BP28(R32), 1, 12, 15, 16, 5, 5.6.2.2, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10, 3.13.11, CCI-000196, CCI-000803, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, 0418, 1055, 1402, A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3, IA-5(c), IA-5(1)(c), CM-6(a), PR.AC-1, PR.AC-6, PR.AC-7, Req-8.2.1, SRG-OS-000073-GPOS-00041, SRG-OS-000120-GPOS-00061, SRG-OS-000480-VMM-002000, 5.4.3, SV-204415r880833_rule


Complexity:low
Disruption:medium
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.6.2.2
  - DISA-STIG-RHEL-07-010200
  - NIST-800-171-3.13.11
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(c)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.1
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - set_password_hashing_algorithm_systemauth

- name: Set PAM's Password Hashing Algorithm - Check if /etc/pam.d/system-auth file
    is present
  ansible.builtin.stat:
    path: /etc/pam.d/system-auth
  register: result_pam_file_present
  when: '"pam" in ansible_facts.packages'
  tags:
  - CJIS-5.6.2.2
  - DISA-STIG-RHEL-07-010200
  - NIST-800-171-3.13.11
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(c)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.1
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - set_password_hashing_algorithm_systemauth

- name: Set PAM's Password Hashing Algorithm - Check the proper remediation for the
    system
  block:

  - name: Set PAM's Password Hashing Algorithm - Define the PAM file to be edited
      as a local fact
    ansible.builtin.set_fact:
      pam_file_path: /etc/pam.d/system-auth

  - name: Set PAM's Password Hashing Algorithm - Check if system relies on authselect
      tool
    ansible.builtin.stat:
      path: /usr/bin/authselect
    register: result_authselect_present

  - name: Set PAM's Password Hashing Algorithm - Ensure authselect custom profile
      is used if authselect is present
    block:

    - name: Set PAM's Password Hashing Algorithm - Check integrity of authselect current
        profile
      ansible.builtin.command:
        cmd: authselect check
      register: result_authselect_check_cmd
      changed_when: false
      ignore_errors: true

    - name: Set PAM's Password Hashing Algorithm - Informative message based on the
        authselect integrity check result
      ansible.builtin.assert:
        that:
        - result_authselect_check_cmd is success
        fail_msg:
        - authselect integrity check failed. Remediation aborted!
        - This remediation could not be applied because an authselect profile was
          not selected or the selected profile is not intact.
        - It is not recommended to manually edit the PAM files when authselect tool
          is available.
        - In cases where the default authselect profile does not cover a specific
          demand, a custom authselect profile is recommended.
        success_msg:
        - authselect integrity check passed

    - name: Set PAM's Password Hashing Algorithm - Get authselect current profile
      ansible.builtin.shell:
        cmd: authselect current -r | awk '{ print $1 }'
      register: result_authselect_profile
      changed_when: false
      when:
      - result_authselect_check_cmd is success

    - name: Set PAM's Password Hashing Algorithm - Define the current authselect profile
        as a local fact
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: '{{ result_authselect_profile.stdout }}'
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is match("custom/")

    - name: Set PAM's Password Hashing Algorithm - Define the new authselect custom
        profile as a local fact
      ansible.builtin.set_fact:
        authselect_current_profile: '{{ result_authselect_profile.stdout }}'
        authselect_custom_profile: custom/hardening
      when:
      - result_authselect_profile is not skipped
      - result_authselect_profile.stdout is not match("custom/")

    - name: Set PAM's Password Hashing Algorithm - Get authselect current features
        to also enable them in the custom profile
      ansible.builtin.shell:
        cmd: authselect current | tail -n+3 | awk '{ print $2 }'
      register: result_authselect_features
      changed_when: false
      when:
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")

    - name: Set PAM's Password Hashing Algorithm - Check if any custom profile with
        the same name was already created
      ansible.builtin.stat:
        path: /etc/authselect/{{ authselect_custom_profile }}
      register: result_authselect_custom_profile_present
      changed_when: false
      when:
      - authselect_current_profile is not match("custom/")

    - name: Set PAM's Password Hashing Algorithm - Create an authselect custom profile
        based on the current profile
      ansible.builtin.command:
        cmd: authselect create-profile hardening -b {{ authselect_current_profile
          }}
      when:
      - result_authselect_check_cmd is success
      - authselect_current_profile is not match("custom/")
      - not result_authselect_custom_profile_present.stat.exists

    - name: Set PAM's Password Hashing Algorithm - Ensure authselect changes are applied
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=before-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: Set PAM's Password Hashing Algorithm - Ensure the authselect custom profile
        is selected
      ansible.builtin.command:
        cmd: authselect select {{ authselect_custom_profile }}
      register: result_pam_authselect_select_profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - authselect_current_profile is not match("custom/")
      - authselect_custom_profile is not match(authselect_current_profile)

    - name: Set PAM's Password Hashing Algorithm - Restore the authselect features
        in the custom profile
      ansible.builtin.command:
        cmd: authselect enable-feature {{ item }}
      loop: '{{ result_authselect_features.stdout_lines }}'
      register: result_pam_authselect_restore_features
      when:
      - result_authselect_profile is not skipped
      - result_authselect_features is not skipped
      - result_pam_authselect_select_profile is not skipped

    - name: Set PAM's Password Hashing Algorithm - Ensure authselect changes are applied
      ansible.builtin.command:
        cmd: authselect apply-changes -b --backup=after-hardening-custom-profile
      when:
      - result_authselect_check_cmd is success
      - result_authselect_profile is not skipped
      - result_pam_authselect_restore_features is not skipped

    - name: Set PAM's Password Hashing Algorithm - Change the PAM file to be edited
        according to the custom authselect profile
      ansible.builtin.set_fact:
        pam_file_path: /etc/authselect/{{ authselect_custom_profile }}/{{ pam_file_path
          | basename }}
    when:
    - result_authselect_present.stat.exists

  - name: Set PAM's Password Hashing Algorithm - Check if expected PAM module line
      is present in {{ pam_file_path }}
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      regexp: ^\s*password\s+sufficient\s+pam_unix.so\s*.*
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_line_present

  - name: Set PAM's Password Hashing Algorithm - Include or update the PAM module
      line in {{ pam_file_path }}
    block:

    - name: Set PAM's Password Hashing Algorithm - Check if required PAM module line
        is present in {{ pam_file_path }} with different control
      ansible.builtin.lineinfile:
        path: '{{ pam_file_path }}'
        regexp: ^\s*password\s+.*\s+pam_unix.so\s*
        state: absent
      check_mode: true
      changed_when: false
      register: result_pam_line_other_control_present

    - name: Set PAM's Password Hashing Algorithm - Ensure the correct control for
        the required PAM module line in {{ pam_file_path }}
      ansible.builtin.replace:
        dest: '{{ pam_file_path }}'
        regexp: ^(\s*password\s+).*(\bpam_unix.so.*)
        replace: \1sufficient \2
      register: result_pam_module_edit
      when:
      - result_pam_line_other_control_present.found == 1

    - name: Set PAM's Password Hashing Algorithm - Ensure the required PAM module
        line is included in {{ pam_file_path }}
      ansible.builtin.lineinfile:
        dest: '{{ pam_file_path }}'
        line: password    sufficient    pam_unix.so
      register: result_pam_module_add
      when:
      - result_pam_line_other_control_present.found == 0 or result_pam_line_other_control_present.found
        > 1

    - name: Set PAM's Password Hashing Algorithm - Ensure authselect changes are applied
      ansible.builtin.command:
        cmd: authselect apply-changes -b
      when: |
        result_authselect_present is defined and result_authselect_present.stat.exists and ((result_pam_module_add is defined and result_pam_module_add.changed) or (result_pam_module_edit is defined and result_pam_module_edit.changed))
    when:
    - result_pam_line_present.found is defined
    - result_pam_line_present.found == 0

  - name: Set PAM's Password Hashing Algorithm - Check if the required PAM module
      option is present in {{ pam_file_path }}
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      regexp: ^\s*password\s+sufficient\s+pam_unix.so\s*.*\ssha512\b
      state: absent
    check_mode: true
    changed_when: false
    register: result_pam_module_sha512_option_present

  - name: Set PAM's Password Hashing Algorithm - Ensure the "sha512" PAM option for
      "pam_unix.so" is included in {{ pam_file_path }}
    ansible.builtin.lineinfile:
      path: '{{ pam_file_path }}'
      backrefs: true
      regexp: ^(\s*password\s+sufficient\s+pam_unix.so.*)
      line: \1 sha512
      state: present
    register: result_pam_sha512_add
    when:
    - result_pam_module_sha512_option_present.found == 0

  - name: Set PAM's Password Hashing Algorithm - Ensure authselect changes are applied
    ansible.builtin.command:
      cmd: authselect apply-changes -b
    when:
    - result_authselect_present.stat.exists
    - (result_pam_sha512_add is defined and result_pam_sha512_add.changed) or (result_pam_sha512_edit
      is defined and result_pam_sha512_edit.changed)
  when:
  - '"pam" in ansible_facts.packages'
  - result_pam_file_present.stat.exists
  tags:
  - CJIS-5.6.2.2
  - DISA-STIG-RHEL-07-010200
  - NIST-800-171-3.13.11
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-5(1)(c)
  - NIST-800-53-IA-5(c)
  - PCI-DSS-Req-8.2.1
  - configure_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - set_password_hashing_algorithm_systemauth


# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

if [ -e "/etc/pam.d/system-auth" ] ; then
    PAM_FILE_PATH="/etc/pam.d/system-auth"
    if [ -f /usr/bin/authselect ]; then
        
        if ! authselect check; then
        echo "
        authselect integrity check failed. Remediation aborted!
        This remediation could not be applied because an authselect profile was not selected or the selected profile is not intact.
        It is not recommended to manually edit the PAM files when authselect tool is available.
        In cases where the default authselect profile does not cover a specific demand, a custom authselect profile is recommended."
        exit 1
        fi

        CURRENT_PROFILE=$(authselect current -r | awk '{ print $1 }')
        # If not already in use, a custom profile is created preserving the enabled features.
        if [[ ! $CURRENT_PROFILE == custom/* ]]; then
            ENABLED_FEATURES=$(authselect current | tail -n+3 | awk '{ print $2 }')
            authselect create-profile hardening -b $CURRENT_PROFILE
            CURRENT_PROFILE="custom/hardening"
            
            authselect apply-changes -b --backup=before-hardening-custom-profile
            authselect select $CURRENT_PROFILE
            for feature in $ENABLED_FEATURES; do
                authselect enable-feature $feature;
            done
            
            authselect apply-changes -b --backup=after-hardening-custom-profile
        fi
        PAM_FILE_NAME=$(basename "/etc/pam.d/system-auth")
        PAM_FILE_PATH="/etc/authselect/$CURRENT_PROFILE/$PAM_FILE_NAME"

        authselect apply-changes -b
    fi
    if ! grep -qP '^\s*password\s+'"sufficient"'\s+pam_unix.so\s*.*' "$PAM_FILE_PATH"; then
            # Line matching group + control + module was not found. Check group + module.
            if [ "$(grep -cP '^\s*password\s+.*\s+pam_unix.so\s*' "$PAM_FILE_PATH")" -eq 1 ]; then
                # The control is updated only if one single line matches.
                sed -i -E --follow-symlinks 's/^(\s*password\s+).*(\bpam_unix.so.*)/\1'"sufficient"' \2/' "$PAM_FILE_PATH"
            else
                echo 'password    '"sufficient"'    pam_unix.so' >> "$PAM_FILE_PATH"
            fi
        fi
        # Check the option
        if ! grep -qP '^\s*password\s+'"sufficient"'\s+pam_unix.so\s*.*\ssha512\b' "$PAM_FILE_PATH"; then
            sed -i -E --follow-symlinks '/\s*password\s+'"sufficient"'\s+pam_unix.so.*/ s/$/ sha512/' "$PAM_FILE_PATH"
        fi
    if [ -f /usr/bin/authselect ]; then
        
        authselect apply-changes -b
    fi
else
    echo "/etc/pam.d/system-auth was not found" >&2
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Protect Physical Console Access   Group contains 2 rules
[ref]   It is impossible to fully protect a system from an attacker with physical access, so securing the space in which the system is located should be considered a necessary step. However, there are some steps which, if taken, make it more difficult for an attacker to quickly or undetectably modify a system from its console.

Rule   Require Authentication for Emergency Systemd Target   [ref]

Emergency mode is intended as a system recovery method, providing a single user root access to the system during a failed boot sequence.

By default, Emergency mode is protected by requiring a password and is set in /usr/lib/systemd/system/emergency.service.
Rationale:
This prevents attackers with physical access from trivially bypassing security on the machine and gaining root access. Such accesses are further prevented by configuring the bootloader password.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_require_emergency_target_auth
Identifiers and References

References:  1, 11, 12, 14, 15, 16, 18, 3, 5, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10, 3.1.1, 3.4.5, CCI-000213, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, IA-2, AC-3, CM-6(a), PR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.PT-3, FIA_UAU.1, SRG-OS-000080-GPOS-00048, 1.4.3


Complexity:low
Disruption:low
Strategy:restrict
- name: require emergency mode password
  lineinfile:
    create: true
    dest: /usr/lib/systemd/system/emergency.service
    regexp: ^#?ExecStart=
    line: ExecStart=-/bin/sh -c "/sbin/sulogin; /usr/bin/systemctl --fail --no-block
      default"
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-171-3.1.1
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-3
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-2
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - require_emergency_target_auth
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

service_file="/usr/lib/systemd/system/emergency.service"

sulogin='/bin/sh -c "/sbin/sulogin; /usr/bin/systemctl --fail --no-block default"'

if grep "^ExecStart=.*" "$service_file" ; then
    sed -i "s%^ExecStart=.*%ExecStart=-$sulogin%" "$service_file"
else
    echo "ExecStart=-$sulogin" >> "$service_file"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Require Authentication for Single User Mode   [ref]

Single-user mode is intended as a system recovery method, providing a single user root access to the system by providing a boot option at startup.

By default, single-user mode is protected by requiring a password and is set in /usr/lib/systemd/system/rescue.service.
Rationale:
This prevents attackers with physical access from trivially bypassing security on the machine and gaining root access. Such accesses are further prevented by configuring the bootloader password.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_require_singleuser_auth
Identifiers and References

References:  1, 11, 12, 14, 15, 16, 18, 3, 5, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10, 3.1.1, 3.4.5, CCI-000213, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, 0421, 0422, 0431, 0974, 1173, 1401, 1504, 1505, 1546, 1557, 1558, 1559, 1560, 1561, A.18.1.4, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3, IA-2, AC-3, CM-6(a), PR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.PT-3, FIA_UAU.1, SRG-OS-000080-GPOS-00048, 1.4.3, SV-204437r603261_rule


Complexity:low
Disruption:low
Strategy:restrict
- name: require single user mode password
  lineinfile:
    create: true
    dest: /usr/lib/systemd/system/rescue.service
    regexp: ^#?ExecStart=
    line: ExecStart=-/bin/sh -c "/usr/sbin/sulogin; /usr/bin/systemctl --fail --no-block
      default"
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - DISA-STIG-RHEL-07-010481
  - NIST-800-171-3.1.1
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-3
  - NIST-800-53-CM-6(a)
  - NIST-800-53-IA-2
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - require_singleuser_auth
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

service_file="/usr/lib/systemd/system/rescue.service"

sulogin='/bin/sh -c "/usr/sbin/sulogin; /usr/bin/systemctl --fail --no-block default"'

if grep "^ExecStart=.*" "$service_file" ; then
    sed -i "s%^ExecStart=.*%ExecStart=-$sulogin%" "$service_file"
else
    echo "ExecStart=-$sulogin" >> "$service_file"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Protect Accounts by Restricting Password-Based Login   Group contains 4 groups and 15 rules
[ref]   Conventionally, Unix shell accounts are accessed by providing a username and password to a login program, which tests these values for correctness using the /etc/passwd and /etc/shadow files. Password-based login is vulnerable to guessing of weak passwords, and to sniffing and man-in-the-middle attacks against passwords entered over a network or at an insecure console. Therefore, mechanisms for accessing accounts by entering usernames and passwords should be restricted to those which are operationally necessary.
Group   Set Account Expiration Parameters   Group contains 2 rules
Group   Set Password Expiration Parameters   Group contains 3 rules
[ref]   The file /etc/login.defs controls several password-related settings. Programs such as passwd, su, and login consult /etc/login.defs to determine behavior with regard to password aging, expiration warnings, and length. See the man page login.defs(5) for more information.

Users should be forced to change their passwords, in order to decrease the utility of compromised passwords. However, the need to change passwords often should be balanced against the risk that users will reuse or write down passwords if forced to change them too often. Forcing password changes every 90-360 days, depending on the environment, is recommended. Set the appropriate value as PASS_MAX_DAYS and apply it to existing accounts with the -M flag.

The PASS_MIN_DAYS (-m) setting prevents password changes for 7 days after the first change, to discourage password cycling. If you use this setting, train users to contact an administrator for an emergency password change in case a new password becomes compromised. The PASS_WARN_AGE (-W) setting gives users 7 days of warnings at login time that their passwords are about to expire.

For example, for each existing human user USER, expiration parameters could be adjusted to a 180 day maximum password age, 7 day minimum password age, and 7 day warning period with the following command: 
$ sudo chage -M 180 -m 7 -W 7 USER
Group   Verify Proper Storage and Existence of Password Hashes   Group contains 3 rules
[ref]   By default, password hashes for local accounts are stored in the second field (colon-separated) in /etc/shadow. This file should be readable only by processes running with root credentials, preventing users from casually accessing others' password hashes and attempting to crack them. However, it remains possible to misconfigure the system and store password hashes in world-readable files such as /etc/passwd, or to even store passwords themselves in plaintext on the system. Using system-provided tools for password change/creation should allow administrators to avoid such misconfiguration.

Rule   Verify All Account Password Hashes are Shadowed   [ref]

If any password hashes are stored in /etc/passwd (in the second field, instead of an x or *), the cause of this misconfiguration should be investigated. The account should have its password reset and the hash should be properly stored, or the account should be deleted entirely.
Rationale:
The hashes for all user account passwords should be stored in the file /etc/shadow and never in /etc/passwd, which is readable by all users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_password_all_shadowed
Identifiers and References

References:  1, 12, 15, 16, 5, 5.5.2, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10, 3.5.10, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, 1410, A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3, IA-5(h), CM-6(a), PR.AC-1, PR.AC-6, PR.AC-7, Req-8.2.1, 6.2.1

Rule   All GIDs referenced in /etc/passwd must be defined in /etc/group   [ref]

Add a group to the system for each GID referenced without a corresponding group.
Rationale:
If a user is assigned the Group Identifier (GID) of a group not existing on the system, and a group with the Group Identifier (GID) is subsequently created, the user may have unintended rights to any files associated with the group.
Severity: 
low
Rule ID:xccdf_org.ssgproject.content_rule_gid_passwd_group_same
Identifiers and References

References:  1, 12, 15, 16, 5, 5.5.2, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.10, CCI-000764, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, A.18.1.4, A.7.1.1, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.2, A.9.4.3, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3, IA-2, CM-6(a), PR.AC-1, PR.AC-6, PR.AC-7, Req-8.5.a, SRG-OS-000104-GPOS-00051, 6.2.3, SV-204461r603261_rule

Rule   Verify No netrc Files Exist   [ref]

The .netrc files contain login information used to auto-login into FTP servers and reside in the user's home directory. These files may contain unencrypted passwords to remote FTP servers making them susceptible to access by unauthorized users and should not be used. Any .netrc files should be removed.
Rationale:
Unencrypted passwords for remote FTP servers may be stored in .netrc files.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_no_netrc_files
Identifiers and References

References:  1, 11, 12, 14, 15, 16, 18, 3, 5, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10, CCI-000196, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, A.18.1.4, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, CIP-003-8 R1.3, CIP-003-8 R3, CIP-003-8 R3.1, CIP-003-8 R3.2, CIP-003-8 R3.3, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3, IA-5(h), IA-5(1)(c), CM-6(a), IA-5(7), PR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.PT-3, 6.2.16

Group   Restrict Root Logins   Group contains 4 rules
[ref]   Direct root logins should be allowed only for emergency use. In normal situations, the administrator should access the system via a unique unprivileged account, and then use su or sudo to execute privileged commands. Discouraging administrators from accessing the root account directly ensures an audit trail in organizations with multiple administrators. Locking down the channels through which root can connect directly also reduces opportunities for password-guessing against the root account. The login program uses the file /etc/securetty to determine which interfaces should allow root logins. The virtual devices /dev/console and /dev/tty* represent the system consoles (accessible via the Ctrl-Alt-F1 through Ctrl-Alt-F6 keyboard sequences on a default installation). The default securetty file also contains /dev/vc/*. These are likely to be deprecated in most environments, but may be retained for compatibility. Root should also be prohibited from connecting via network protocols. Other sections of this document include guidance describing how to prevent root from logging in via SSH.

Rule   Verify Only Root Has UID 0   [ref]

If any account other than root has a UID of 0, this misconfiguration should be investigated and the accounts other than root should be removed or have their UID changed.
If the account is associated with system commands or applications the UID should be changed to one greater than "0" but less than "1000." Otherwise assign a UID greater than "1000" that has not already been assigned.
Rationale:
An account has root authority if it has a UID of 0. Multiple accounts with a UID of 0 afford more opportunity for potential intruders to guess a password for a privileged account. Proper configuration of sudo is recommended to afford multiple system administrators access to root privileges in an accountable manner.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_accounts_no_uid_except_zero
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 18, 3, 5, APO01.06, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.02, DSS06.03, DSS06.10, 3.1.1, 3.1.5, CCI-000366, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.18.1.4, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.2.3, CIP-004-6 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.2, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3, IA-2, AC-6(5), IA-4(b), PR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.DS-5, Req-8.2.1, SRG-OS-000480-GPOS-00227, 6.2.9, SV-204462r603261_rule


Complexity:low
Disruption:low
Strategy:restrict
- name: get all /etc/passwd file entries
  getent:
    database: passwd
    split: ':'
  tags:
  - DISA-STIG-RHEL-07-020310
  - NIST-800-171-3.1.1
  - NIST-800-171-3.1.5
  - NIST-800-53-AC-6(5)
  - NIST-800-53-IA-2
  - NIST-800-53-IA-4(b)
  - PCI-DSS-Req-8.2.1
  - accounts_no_uid_except_zero
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - restrict_strategy

- name: lock the password of the user accounts other than root with uid 0
  command: passwd -l {{ item.key }}
  loop: '{{ getent_passwd | dict2items | rejectattr(''key'', ''search'', ''root'')
    | list }}'
  when: item.value.1  == '0'
  tags:
  - DISA-STIG-RHEL-07-020310
  - NIST-800-171-3.1.1
  - NIST-800-171-3.1.5
  - NIST-800-53-AC-6(5)
  - NIST-800-53-IA-2
  - NIST-800-53-IA-4(b)
  - PCI-DSS-Req-8.2.1
  - accounts_no_uid_except_zero
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - restrict_strategy


awk -F: '$3 == 0 && $1 != "root" { print $1 }' /etc/passwd | xargs --no-run-if-empty --max-lines=1 passwd -l

Rule   Verify Root Has A Primary GID 0   [ref]

The root user should have a primary group of 0.
Rationale:
To help ensure that root-owned files are not inadvertently exposed to other users.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_accounts_root_gid_zero
Identifiers and References

References:  Req-8.2.1, 5.5.3

Rule   Ensure that System Accounts Do Not Run a Shell Upon Login   [ref]

Some accounts are not associated with a human user of the system, and exist to perform some administrative function. Should an attacker be able to log into these accounts, they should not be granted access to a shell.

The login shell for each local account is stored in the last field of each line in /etc/passwd. System accounts are those user accounts with a user ID less than UID_MIN, where value of UID_MIN directive is set in /etc/login.defs configuration file. In the default configuration UID_MIN is set to 1000, thus system accounts are those user accounts with a user ID less than 1000. The user ID is stored in the third field. If any system account SYSACCT (other than root) has a login shell, disable it with the command: 
$ sudo usermod -s /sbin/nologin SYSACCT
Warning:  Do not perform the steps in this section on the root account. Doing so might cause the system to become inaccessible.
Rationale:
Ensuring shells are not given to system accounts upon login makes it more difficult for attackers to make use of system accounts.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_no_shelllogin_for_systemaccounts
Identifiers and References

References:  1, 12, 13, 14, 15, 16, 18, 3, 5, 7, 8, DSS01.03, DSS03.05, DSS05.04, DSS05.05, DSS05.07, DSS06.03, CCI-000366, 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, SR 1.1, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 6.2, 1491, A.12.4.1, A.12.4.3, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, AC-6, CM-6(a), CM-6(b), CM-6.1(iv), DE.CM-1, DE.CM-3, PR.AC-1, PR.AC-4, PR.AC-6, Req-8.6.1, SRG-OS-000480-GPOS-00227, 5.5.2

Rule   Enforce usage of pam_wheel for su authentication   [ref]

To ensure that only users who are members of the wheel group can run commands with altered privileges through the su command, make sure that the following line exists in the file /etc/pam.d/su: 
auth required pam_wheel.so use_uid
Warning:  Members of "wheel" or GID 0 groups are checked by default if the group option is not set for pam_wheel.so module. Therefore, members of these groups should be manually checked or a different group should be informed according to the site policy.
Rationale:
The su program allows to run commands with a substitute user and group ID. It is commonly used to run commands as the root user. Limiting access to such command is considered a good security practice.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_use_pam_wheel_for_su
Identifiers and References

References:  FMT_SMF_EXT.1.1, Req-8.6.1, SRG-OS-000373-GPOS-00156, SRG-OS-000312-GPOS-00123, 5.7


Complexity:low
Disruption:low
Strategy:restrict
- name: restrict usage of su command only to members of wheel group
  replace:
    path: /etc/pam.d/su
    regexp: ^[\s]*#[\s]*auth[\s]+required[\s]+pam_wheel\.so[\s]+use_uid$
    replace: auth             required        pam_wheel.so use_uid
  tags:
  - PCI-DSS-Req-8.6.1
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - use_pam_wheel_for_su



# uncomment the option if commented
  sed '/^[[:space:]]*#[[:space:]]*auth[[:space:]]\+required[[:space:]]\+pam_wheel\.so[[:space:]]\+use_uid$/s/^[[:space:]]*#//' -i /etc/pam.d/su

Rule   Ensure All Groups on the System Have Unique Group ID   [ref]

Change the group name or delete groups, so each has a unique id.
Warning:  Automatic remediation of this control is not available due to the unique requirements of each system.
Rationale:
To assure accountability and prevent unauthenticated access, groups must be identified uniquely to prevent potential misuse and compromise of the system.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_group_unique_id
Identifiers and References

References:  CCI-000764, SRG-OS-000104-GPOS-00051, 6.2.7

Rule   Ensure All Groups on the System Have Unique Group Names   [ref]

Change the group name or delete groups, so each has a unique name.
Warning:  Automatic remediation of this control is not available due to the unique requirements of each system.
Rationale:
To assure accountability and prevent unauthenticated access, groups must be identified uniquely to prevent potential misuse and compromise of the system.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_group_unique_name
Identifiers and References

References:  6.2.6

Group   Secure Session Configuration Files for Login Accounts   Group contains 2 groups and 9 rules
[ref]   When a user logs into a Unix account, the system configures the user's session by reading a number of files. Many of these files are located in the user's home directory, and may have weak permissions as a result of user error or misconfiguration. If an attacker can modify or even read certain types of account configuration information, they can often gain full access to the affected user's account. Therefore, it is important to test and correct configuration file permissions for interactive accounts, particularly those of privileged users such as root or system administrators.
Group   Ensure that No Dangerous Directories Exist in Root's Path   Group contains 2 rules
[ref]   The active path of the root account can be obtained by starting a new root shell and running: 
# echo $PATH
This will produce a colon-separated list of directories in the path.

Certain path elements could be considered dangerous, as they could lead to root executing unknown or untrusted programs, which could contain malicious code. Since root may sometimes work inside untrusted directories, the . character, which represents the current directory, should never be in the root path, nor should any directory which can be written to by an unprivileged or semi-privileged (system) user.

It is a good practice for administrators to always execute privileged commands by typing the full path to the command.

Rule   Ensure that Root's Path Does Not Include World or Group-Writable Directories   [ref]

For each element in root's path, run: 
# ls -ld DIR
and ensure that write permissions are disabled for group and other.
Rationale:
Such entries increase the risk that root could execute code provided by unprivileged users, and potentially malicious code.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_root_path_dirs_no_write
Identifiers and References

References:  11, 3, 9, BAI10.01, BAI10.02, BAI10.03, BAI10.05, CCI-000366, 4.3.4.3.2, 4.3.4.3.3, SR 7.6, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, CM-6(a), CM-6(a), PR.IP-1, 6.2.10


Complexity:low
Disruption:medium
Strategy:restrict
- name: Print error message if user is not root
  fail:
    msg: Root account required to read root $PATH
  when: ansible_env.USER != "root"
  ignore_errors: true
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(a)
  - accounts_root_path_dirs_no_write
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Get root paths which are not symbolic links
  stat:
    path: '{{ item }}'
  changed_when: false
  failed_when: false
  register: root_paths
  with_items: '{{ ansible_env.PATH.split('':'') }}'
  when: ansible_env.USER == "root"
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(a)
  - accounts_root_path_dirs_no_write
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Disable writability to root directories
  file:
    path: '{{ item.item }}'
    mode: g-w,o-w
  with_items: '{{ root_paths.results }}'
  when:
  - root_paths.results is defined
  - item.stat.exists
  - not item.stat.islnk
  tags:
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-6(a)
  - accounts_root_path_dirs_no_write
  - low_complexity
  - medium_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Rule   Ensure that Root's Path Does Not Include Relative Paths or Null Directories   [ref]

Ensure that none of the directories in root's path is equal to a single . character, or that it contains any instances that lead to relative path traversal, such as .. or beginning a path without the slash (/) character. Also ensure that there are no "empty" elements in the path, such as in these examples: 
PATH=:/bin
PATH=/bin:
PATH=/bin::/sbin
These empty elements have the same effect as a single . character.
Rationale:
Including these entries increases the risk that root could execute code from an untrusted location.
Severity: 
unknown
Rule ID:xccdf_org.ssgproject.content_rule_root_path_no_dot
Identifiers and References

References:  11, 3, 9, BAI10.01, BAI10.02, BAI10.03, BAI10.05, CCI-000366, 4.3.4.3.2, 4.3.4.3.3, SR 7.6, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, CM-6(a), CM-6(a), PR.IP-1, 6.2.10

Group   Ensure that Users Have Sensible Umask Values   Group contains 3 rules
[ref]   The umask setting controls the default permissions for the creation of new files. With a default umask setting of 077, files and directories created by users will not be readable by any other user on the system. Users who wish to make specific files group- or world-readable can accomplish this by using the chmod command. Additionally, users can make all their files readable to their group by default by setting a umask of 027 in their shell configuration files. If default per-user groups exist (that is, if every user has a default group whose name is the same as that user's username and whose only member is the user), then it may even be safe for users to select a umask of 007, making it very easy to intentionally share files with groups of which the user is a member.

Rule   Ensure the Default Bash Umask is Set Correctly   [ref]

To ensure the default umask for users of the Bash shell is set properly, add or correct the umask setting in /etc/bashrc to read as follows: 
umask 027
Rationale:
The umask value influences the permissions assigned to files when they are created. A misconfigured umask value could result in files with excessive permissions that can be read or written to by unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_umask_etc_bashrc
Identifiers and References

References:  BP28(R35), 18, APO13.01, BAI03.01, BAI03.02, BAI03.03, CCI-000366, 4.3.4.3.3, A.14.1.1, A.14.2.1, A.14.2.5, A.6.1.5, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.3, CIP-007-3 R2.1, CIP-007-3 R2.2, CIP-007-3 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.1, CIP-007-3 R5.1.2, AC-6(1), CM-6(a), PR.IP-2, Req-8.6.1, SRG-OS-000480-GPOS-00228, SRG-OS-000480-GPOS-00227, 5.5.5


Complexity:low
Disruption:low
Strategy:restrict
- name: XCCDF Value var_accounts_user_umask # promote to variable
  set_fact:
    var_accounts_user_umask: !!str 027
  tags:
    - always

- name: Check if umask in /etc/bashrc is already set
  ansible.builtin.lineinfile:
    path: /etc/bashrc
    regexp: ^(\s*)umask\s+.*
    state: absent
  check_mode: true
  changed_when: false
  register: umask_replace
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.6.1
  - accounts_umask_etc_bashrc
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Replace user umask in /etc/bashrc
  ansible.builtin.replace:
    path: /etc/bashrc
    regexp: ^(\s*)umask(\s+).*
    replace: \g<1>umask\g<2>{{ var_accounts_user_umask }}
  when: umask_replace.found > 0
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.6.1
  - accounts_umask_etc_bashrc
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure the Default umask is Appended Correctly
  ansible.builtin.lineinfile:
    create: true
    path: /etc/bashrc
    line: umask {{ var_accounts_user_umask }}
  when: umask_replace.found == 0
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.6.1
  - accounts_umask_etc_bashrc
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy



var_accounts_user_umask='027'






grep -q "^\s*umask" /etc/bashrc && \
  sed -i -E -e "s/^(\s*umask).*/\1 $var_accounts_user_umask/g" /etc/bashrc
if ! [ $? -eq 0 ]; then
    echo "umask $var_accounts_user_umask" >> /etc/bashrc
fi

Rule   Ensure the Default Umask is Set Correctly in /etc/profile   [ref]

To ensure the default umask controlled by /etc/profile is set properly, add or correct the umask setting in /etc/profile to read as follows: 
umask 027
Rationale:
The umask value influences the permissions assigned to files when they are created. A misconfigured umask value could result in files with excessive permissions that can be read or written to by unauthorized users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_umask_etc_profile
Identifiers and References

References:  BP28(R35), 18, APO13.01, BAI03.01, BAI03.02, BAI03.03, CCI-000366, 4.3.4.3.3, A.14.1.1, A.14.2.1, A.14.2.5, A.6.1.5, CIP-003-8 R5.1.1, CIP-003-8 R5.3, CIP-004-6 R2.3, CIP-007-3 R2.1, CIP-007-3 R2.2, CIP-007-3 R2.3, CIP-007-3 R5.1, CIP-007-3 R5.1.1, CIP-007-3 R5.1.2, AC-6(1), CM-6(a), PR.IP-2, Req-8.6.1, SRG-OS-000480-GPOS-00228, SRG-OS-000480-GPOS-00227, 5.5.5


Complexity:low
Disruption:low
Strategy:restrict
- name: XCCDF Value var_accounts_user_umask # promote to variable
  set_fact:
    var_accounts_user_umask: !!str 027
  tags:
    - always

- name: Check if umask is already set
  ansible.builtin.lineinfile:
    path: /etc/profile
    regexp: (^[\s]*umask)\s+(\d+)
    state: absent
  check_mode: true
  changed_when: false
  register: result_umask_is_set
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.6.1
  - accounts_umask_etc_profile
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Replace user umask in /etc/profile
  ansible.builtin.replace:
    path: /etc/profile
    regexp: ^(\s*)umask\s+\d+
    replace: \1umask {{ var_accounts_user_umask }}
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.6.1
  - accounts_umask_etc_profile
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Append user umask in /etc/profile
  ansible.builtin.lineinfile:
    create: true
    path: /etc/profile
    line: umask {{ var_accounts_user_umask }}
  when: result_umask_is_set.found == 0
  tags:
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-8.6.1
  - accounts_umask_etc_profile
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy



var_accounts_user_umask='027'


grep -qE '^[^#]*umask' /etc/profile && \
  sed -i "s/umask.*/umask $var_accounts_user_umask/g" /etc/profile
if ! [ $? -eq 0 ]; then
    echo "umask $var_accounts_user_umask" >> /etc/profile
fi

Rule   Set Interactive Session Timeout   [ref]

Setting the TMOUT option in /etc/profile ensures that all user sessions will terminate based on inactivity. The value of TMOUT should be exported and read only. The TMOUT setting in a file loaded by /etc/profileor /etc/bashrc, e.g. /etc/profile.d/tmout.sh should read as follows: 
declare -xr TMOUT=900
Rationale:
Terminating an idle session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or console port that has been left unattended.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_tmout
Identifiers and References

References:  BP28(R29), 1, 12, 15, 16, DSS05.04, DSS05.10, DSS06.10, 3.1.11, CCI-000057, CCI-001133, CCI-002361, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, SR 1.1, SR 1.10, SR 1.2, SR 1.5, SR 1.7, SR 1.8, SR 1.9, A.18.1.4, A.9.2.1, A.9.2.4, A.9.3.1, A.9.4.2, A.9.4.3, CIP-004-6 R2.2.3, CIP-007-3 R5.1, CIP-007-3 R5.2, CIP-007-3 R5.3.1, CIP-007-3 R5.3.2, CIP-007-3 R5.3.3, AC-12, SC-10, AC-2(5), CM-6(a), PR.AC-7, FMT_MOF_EXT.1, Req-8.6.1, SRG-OS-000163-GPOS-00072, SRG-OS-000029-GPOS-00010, SRG-OS-000163-VMM-000700, SRG-OS-000279-VMM-001010, 5.5.4, SV-204579r861070_rule


Complexity:low
Disruption:low
Strategy:restrict
- name: XCCDF Value var_accounts_tmout # promote to variable
  set_fact:
    var_accounts_tmout: !!str 900
  tags:
    - always

- name: Correct any occurrence of TMOUT in /etc/bashrc
  replace:
    path: /etc/bashrc
    regexp: ^[^#].*TMOUT=.*
    replace: declare -xr TMOUT={{ var_accounts_tmout }}
  register: bashrc_replaced
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - DISA-STIG-RHEL-07-040160
  - NIST-800-171-3.1.11
  - NIST-800-53-AC-12
  - NIST-800-53-AC-2(5)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-10
  - PCI-DSS-Req-8.6.1
  - accounts_tmout
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Correct any occurrence of TMOUT in /etc/profile
  replace:
    path: /etc/profile
    regexp: ^[^#].*TMOUT=.*
    replace: declare -xr TMOUT={{ var_accounts_tmout }}
  register: profile_replaced
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - DISA-STIG-RHEL-07-040160
  - NIST-800-171-3.1.11
  - NIST-800-53-AC-12
  - NIST-800-53-AC-2(5)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-10
  - PCI-DSS-Req-8.6.1
  - accounts_tmout
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Set Interactive Session Timeout
  lineinfile:
    path: /etc/profile.d/tmout.sh
    create: true
    regexp: TMOUT=
    line: declare -xr TMOUT={{ var_accounts_tmout }}
    state: present
  when:
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - profile_replaced is defined and not profile_replaced.changed and bashrc_replaced
    is defined and not bashrc_replaced.changed
  tags:
  - DISA-STIG-RHEL-07-040160
  - NIST-800-171-3.1.11
  - NIST-800-53-AC-12
  - NIST-800-53-AC-2(5)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-SC-10
  - PCI-DSS-Req-8.6.1
  - accounts_tmout
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

var_accounts_tmout='900'


# if 0, no occurence of tmout found, if 1, occurence found
tmout_found=0


for f in /etc/profile /etc/profile.d/*.sh /etc/bashrc; do

    if grep --silent '^[^#].*TMOUT' $f; then
        sed -i -E "s/^(.*)TMOUT\s*=\s*(\w|\$)*(.*)$/declare -xr TMOUT=$var_accounts_tmout\3/g" $f
        tmout_found=1
    fi
done

if [ $tmout_found -eq 0 ]; then
        echo -e "\n# Set TMOUT to $var_accounts_tmout per security requirements" >> /etc/profile.d/tmout.sh
        echo "declare -xr TMOUT=$var_accounts_tmout" >> /etc/profile.d/tmout.sh
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   All Interactive Users Home Directories Must Exist   [ref]

Create home directories to all interactive users that currently do not have a home directory assigned. Use the following commands to create the user home directory assigned in /etc/passwd: 
$ sudo mkdir /home/USER
Rationale:
If a local interactive user has a home directory defined that does not exist, the user may be given access to the / directory as the current working directory upon logon. This could create a Denial of Service because the user would not be able to access their logon configuration files, and it may give them visibility to system files they normally would not be able to access.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_accounts_user_interactive_home_directory_exists
Identifiers and References

References:  CCI-000366, SRG-OS-000480-GPOS-00227, 6.2.11, SV-204467r603826_rule


Complexity:low
Disruption:low
Strategy:restrict
- name: Get all local users from /etc/passwd
  ansible.builtin.getent:
    database: passwd
    split: ':'
  tags:
  - DISA-STIG-RHEL-07-020620
  - accounts_user_interactive_home_directory_exists
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Create local_users variable from the getent output
  ansible.builtin.set_fact:
    local_users: '{{ ansible_facts.getent_passwd|dict2items }}'
  tags:
  - DISA-STIG-RHEL-07-020620
  - accounts_user_interactive_home_directory_exists
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure interactive users have a home directory exists
  ansible.builtin.user:
    name: '{{ item.key }}'
    create_home: true
  loop: '{{ local_users }}'
  when:
  - item.value[2]|int >= 1000
  - item.value[2]|int != 65534
  tags:
  - DISA-STIG-RHEL-07-020620
  - accounts_user_interactive_home_directory_exists
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Complexity:low
Disruption:low
Strategy:restrict

for user in $(awk -F':' '{ if ($3 >= 1000 && $3 != 65534) print $1}' /etc/passwd); do
    mkhomedir_helper $user 0077;
done

Rule   All Interactive User Home Directories Must Be Owned By The Primary User   [ref]

Change the owner of interactive users home directories to that correct owner. To change the owner of a interactive users home directory, use the following command: 
$ sudo chown USER /home/USER
This rule ensures every home directory related to an interactive user is owned by an interactive user. It also ensures that interactive users are owners of one and only one home directory.
Warning:  Due to OVAL limitation, this rule can report a false negative in a specific situation where two interactive users swap the ownership of their respective home directories.
Rationale:
If a local interactive user does not own their home directory, unauthorized users could access or modify the user's files, and the users may not be able to access their own files.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_ownership_home_directories
Identifiers and References

References:  CCI-000366, SRG-OS-000480-GPOS-00227, 6.2.12, SV-204469r603830_rule


Complexity:low
Disruption:low
Strategy:restrict
- name: Get all local users from /etc/passwd
  ansible.builtin.getent:
    database: passwd
    split: ':'
  tags:
  - DISA-STIG-RHEL-07-020640
  - file_ownership_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Create local_users variable from the getent output
  ansible.builtin.set_fact:
    local_users: '{{ ansible_facts.getent_passwd|dict2items }}'
  tags:
  - DISA-STIG-RHEL-07-020640
  - file_ownership_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Test for existence home directories to avoid creating them, but only fixing
    ownership
  ansible.builtin.stat:
    path: '{{ item.value[4] }}'
  register: path_exists
  loop: '{{ local_users }}'
  when:
  - item.value[1]|int >= 1000
  - item.value[1]|int != 65534
  tags:
  - DISA-STIG-RHEL-07-020640
  - file_ownership_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure interactive local users are the owners of their respective home directories
  ansible.builtin.file:
    path: '{{ item.0.value[4] }}'
    owner: '{{ item.0.value[1] }}'
  loop: '{{ local_users|zip(path_exists.results)|list }}'
  when: item.1.stat is defined and item.1.stat.exists
  tags:
  - DISA-STIG-RHEL-07-020640
  - file_ownership_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Complexity:low
Disruption:low
Strategy:restrict

awk -F':' '{ if ($3 >= 1000 && $3 != 65534) system("chown -f " $3" "$6) }' /etc/passwd

Rule   All Interactive User Home Directories Must Have mode 0750 Or Less Permissive   [ref]

Change the mode of interactive users home directories to 0750. To change the mode of interactive users home directory, use the following command: 
$ sudo chmod 0750 /home/USER
Rationale:
Excessive permissions on local interactive user home directories may allow unauthorized access to user files by other users.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_home_directories
Identifiers and References

References:  CCI-000366, SRG-OS-000480-GPOS-00227, 6.2.13, SV-204468r603828_rule


Complexity:low
Disruption:low
Strategy:restrict
- name: Get all local users from /etc/passwd
  ansible.builtin.getent:
    database: passwd
    split: ':'
  tags:
  - DISA-STIG-RHEL-07-020630
  - file_permissions_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Create local_users variable from the getent output
  ansible.builtin.set_fact:
    local_users: '{{ ansible_facts.getent_passwd|dict2items }}'
  tags:
  - DISA-STIG-RHEL-07-020630
  - file_permissions_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Test for existence home directories to avoid creating them.
  ansible.builtin.stat:
    path: '{{ item.value[4] }}'
  register: path_exists
  loop: '{{ local_users }}'
  when:
  - item.value[1]|int >= 1000
  - item.value[1]|int != 65534
  tags:
  - DISA-STIG-RHEL-07-020630
  - file_permissions_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

- name: Ensure interactive local users have proper permissions on their respective
    home directories
  ansible.builtin.file:
    path: '{{ item.0.value[4] }}'
    mode: u-s,g-w-s,o=-
    follow: false
    recurse: false
  loop: '{{ local_users|zip(path_exists.results)|list }}'
  when: item.1.stat is defined and item.1.stat.exists
  tags:
  - DISA-STIG-RHEL-07-020630
  - file_permissions_home_directories
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Complexity:low
Disruption:low
Strategy:restrict

for home_dir in $(awk -F':' '{ if ($3 >= 1000 && $3 != 65534) print $6 }' /etc/passwd); do
    # Only update the permissions when necessary. This will avoid changing the inode timestamp when
    # the permission is already defined as expected, therefore not impacting in possible integrity
    # check systems that also check inodes timestamps.
    find "$home_dir" -maxdepth 0 -perm /7027 -exec chmod u-s,g-w-s,o=- {} \;
done
Group   GRUB2 bootloader configuration   Group contains 2 groups and 14 rules
[ref]   During the boot process, the boot loader is responsible for starting the execution of the kernel and passing options to it. The boot loader allows for the selection of different kernels - possibly on different partitions or media. The default Red Hat Enterprise Linux 7 boot loader for x86 systems is called GRUB2. Options it can pass to the kernel include single-user mode, which provides root access without any authentication, and the ability to disable SELinux. To prevent local users from modifying the boot parameters and endangering security, protect the boot loader configuration with a password and ensure its configuration file's permissions are set properly.
Group   Non-UEFI GRUB2 bootloader configuration   Group contains 7 rules
[ref]   Non-UEFI GRUB2 bootloader configuration

Rule   Verify /boot/grub2/grub.cfg Group Ownership   [ref]

The file /boot/grub2/grub.cfg should be group-owned by the root group to prevent destruction or modification of the file. To properly set the group owner of /boot/grub2/grub.cfg, run the command: 
$ sudo chgrp root /boot/grub2/grub.cfg
Rationale:
The root group is a highly-privileged group. Furthermore, the group-owner of this file should not have any access privileges anyway.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_grub2_cfg
Identifiers and References

References:  12, 13, 14, 15, 16, 18, 3, 5, 5.5.2.2, APO01.06, DSS05.04, DSS05.07, DSS06.02, 3.4.5, CCI-000225, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.7.3, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), AC-6(1), PR.AC-4, PR.DS-5, Req-7.1, SRG-OS-000480-GPOS-00227, 1.4.2


Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_groupowner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/grub2/grub.cfg
  stat:
    path: /boot/grub2/grub.cfg
  register: file_exists
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_groupowner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /boot/grub2/grub.cfg
  file:
    path: /boot/grub2/grub.cfg
    group: '0'
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_groupowner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure
# Remediation is applicable only in certain platforms
if [ ! -f /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chgrp 0 /boot/grub2/grub.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Verify /boot/grub2/user.cfg Group Ownership   [ref]

The file /boot/grub2/user.cfg should be group-owned by the root group to prevent reading or modification of the file. To properly set the group owner of /boot/grub2/user.cfg, run the command: 
$ sudo chgrp root /boot/grub2/user.cfg
Rationale:
The root group is a highly-privileged group. Furthermore, the group-owner of this file should not have any access privileges anyway. Non-root users who read the boot parameters may be able to identify weaknesses in security upon boot and be able to exploit them.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_user_cfg
Identifiers and References

References:  12, 13, 14, 15, 16, 18, 3, 5, 5.5.2.2, APO01.06, DSS05.04, DSS05.07, DSS06.02, 3.4.5, CCI-000225, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.7.3, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), AC-6(1), PR.AC-4, PR.DS-5, Req-7.1, SRG-OS-000480-GPOS-00227, 1.4.2


Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_groupowner_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/grub2/user.cfg
  stat:
    path: /boot/grub2/user.cfg
  register: file_exists
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_groupowner_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /boot/grub2/user.cfg
  file:
    path: /boot/grub2/user.cfg
    group: '0'
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_groupowner_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure
# Remediation is applicable only in certain platforms
if [ ! -f /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chgrp 0 /boot/grub2/user.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Verify /boot/grub2/grub.cfg User Ownership   [ref]

The file /boot/grub2/grub.cfg should be owned by the root user to prevent destruction or modification of the file. To properly set the owner of /boot/grub2/grub.cfg, run the command: 
$ sudo chown root /boot/grub2/grub.cfg
Rationale:
Only root should be able to modify important boot parameters.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_grub2_cfg
Identifiers and References

References:  12, 13, 14, 15, 16, 18, 3, 5, 5.5.2.2, APO01.06, DSS05.04, DSS05.07, DSS06.02, 3.4.5, CCI-000225, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.7.3, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), AC-6(1), PR.AC-4, PR.DS-5, Req-7.1, 1.4.2


Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_owner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/grub2/grub.cfg
  stat:
    path: /boot/grub2/grub.cfg
  register: file_exists
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_owner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /boot/grub2/grub.cfg
  file:
    path: /boot/grub2/grub.cfg
    owner: '0'
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_owner_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure
# Remediation is applicable only in certain platforms
if [ ! -f /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chown 0 /boot/grub2/grub.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Verify /boot/grub2/user.cfg User Ownership   [ref]

The file /boot/grub2/user.cfg should be owned by the root user to prevent reading or modification of the file. To properly set the owner of /boot/grub2/user.cfg, run the command: 
$ sudo chown root /boot/grub2/user.cfg
Rationale:
Only root should be able to modify important boot parameters. Also, non-root users who read the boot parameters may be able to identify weaknesses in security upon boot and be able to exploit them.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_user_cfg
Identifiers and References

References:  12, 13, 14, 15, 16, 18, 3, 5, 5.5.2.2, APO01.06, DSS05.04, DSS05.07, DSS06.02, 3.4.5, CCI-000225, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.7.3, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), AC-6(1), PR.AC-4, PR.DS-5, Req-7.1, 1.4.2


Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_owner_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/grub2/user.cfg
  stat:
    path: /boot/grub2/user.cfg
  register: file_exists
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_owner_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /boot/grub2/user.cfg
  file:
    path: /boot/grub2/user.cfg
    owner: '0'
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_owner_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure
# Remediation is applicable only in certain platforms
if [ ! -f /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chown 0 /boot/grub2/user.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Verify /boot/grub2/grub.cfg Permissions   [ref]

File permissions for /boot/grub2/grub.cfg should be set to 600. To properly set the permissions of /boot/grub2/grub.cfg, run the command: 
$ sudo chmod 600 /boot/grub2/grub.cfg
Rationale:
Proper permissions ensure that only the root user can modify important boot parameters.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_grub2_cfg
Identifiers and References

References:  12, 13, 14, 15, 16, 18, 3, 5, APO01.06, DSS05.04, DSS05.07, DSS06.02, 3.4.5, CCI-000225, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.7.3, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), AC-6(1), PR.AC-4, PR.DS-5, 1.4.2


Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/grub2/grub.cfg
  stat:
    path: /boot/grub2/grub.cfg
  register: file_exists
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xwrs,o-xwrt on /boot/grub2/grub.cfg
  file:
    path: /boot/grub2/grub.cfg
    mode: u-xs,g-xwrs,o-xwrt
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure
# Remediation is applicable only in certain platforms
if [ ! -f /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chmod u-xs,g-xwrs,o-xwrt /boot/grub2/grub.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Verify /boot/grub2/user.cfg Permissions   [ref]

File permissions for /boot/grub2/user.cfg should be set to 600. To properly set the permissions of /boot/grub2/user.cfg, run the command: 
$ sudo chmod 600 /boot/grub2/user.cfg
Rationale:
Proper permissions ensure that only the root user can read or modify important boot parameters.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_user_cfg
Identifiers and References

References:  12, 13, 14, 15, 16, 18, 3, 5, APO01.06, DSS05.04, DSS05.07, DSS06.02, 3.4.5, CCI-000225, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.7.3, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), AC-6(1), PR.AC-4, PR.DS-5, 1.4.2


Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/grub2/user.cfg
  stat:
    path: /boot/grub2/user.cfg
  register: file_exists
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xwrs,o-xwrt on /boot/grub2/user.cfg
  file:
    path: /boot/grub2/user.cfg
    mode: u-xs,g-xwrs,o-xwrt
  when:
  - '"/boot/efi" not in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure
# Remediation is applicable only in certain platforms
if [ ! -f /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chmod u-xs,g-xwrs,o-xwrt /boot/grub2/user.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Set Boot Loader Password in grub2   [ref]

The grub2 boot loader should have a superuser account and password protection enabled to protect boot-time settings.

Since plaintext passwords are a security risk, generate a hash for the password by running the following command: 
# grub2-setpassword
When prompted, enter the password that was selected.

Warning:  To prevent hard-coded passwords, automatic remediation of this control is not available. Remediation must be automated as a component of machine provisioning, or followed manually as outlined above. Also, do NOT manually add the superuser account and password to the grub.cfg file as the grub2-mkconfig command overwrites this file.
Rationale:
Password protection on the boot loader configuration ensures users with physical access cannot trivially alter important bootloader settings. These include which kernel to use, and whether to enter single-user mode.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_grub2_password
Identifiers and References

References:  BP28(R17), 1, 11, 12, 14, 15, 16, 18, 3, 5, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS05.10, DSS06.03, DSS06.06, DSS06.10, 3.4.5, CCI-000213, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, A.18.1.4, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.2, A.9.2.3, A.9.2.4, A.9.2.6, A.9.3.1, A.9.4.1, A.9.4.2, A.9.4.3, A.9.4.4, A.9.4.5, CM-6(a), PR.AC-1, PR.AC-4, PR.AC-6, PR.AC-7, PR.PT-3, FIA_UAU.1, SRG-OS-000080-GPOS-00048, 1.4.1, SV-204438r744095_rule

Group   UEFI GRUB2 bootloader configuration   Group contains 7 rules
[ref]   UEFI GRUB2 bootloader configuration

Rule   Verify the UEFI Boot Loader grub.cfg Group Ownership   [ref]

The file /boot/efi/EFI/redhat/grub.cfg should be group-owned by the root group to prevent destruction or modification of the file. To properly set the group owner of /boot/efi/EFI/redhat/grub.cfg, run the command: 
$ sudo chgrp root /boot/efi/EFI/redhat/grub.cfg
Rationale:
The root group is a highly-privileged group. Furthermore, the group-owner of this file should not have any access privileges anyway.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_efi_grub2_cfg
Identifiers and References

References:  12, 13, 14, 15, 16, 18, 3, 5, 5.5.2.2, APO01.06, DSS05.04, DSS05.07, DSS06.02, 3.4.5, CCI-000225, 4.3.3.7.3, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), AC-6(1), PR.AC-4, PR.DS-5, Req-7.1, 1.4.2


Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_groupowner_efi_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/efi/EFI/redhat/grub.cfg
  stat:
    path: /boot/efi/EFI/redhat/grub.cfg
  register: file_exists
  when:
  - '"/boot/efi" in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_groupowner_efi_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /boot/efi/EFI/redhat/grub.cfg
  file:
    path: /boot/efi/EFI/redhat/grub.cfg
    group: '0'
  when:
  - '"/boot/efi" in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_groupowner_efi_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure
# Remediation is applicable only in certain platforms
if [ -f /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chgrp 0 /boot/efi/EFI/redhat/grub.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Verify /boot/efi/EFI/redhat/user.cfg Group Ownership   [ref]

The file /boot/efi/EFI/redhat/user.cfg should be group-owned by the root group to prevent reading or modification of the file. To properly set the group owner of /boot/efi/EFI/redhat/user.cfg, run the command: 
$ sudo chgrp root /boot/efi/EFI/redhat/user.cfg
Rationale:
The root group is a highly-privileged group. Furthermore, the group-owner of this file should not have any access privileges anyway. Non-root users who read the boot parameters may be able to identify weaknesses in security upon boot and be able to exploit them.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_efi_user_cfg
Identifiers and References

References:  12, 13, 14, 15, 16, 18, 3, 5, 5.5.2.2, APO01.06, DSS05.04, DSS05.07, DSS06.02, 3.4.5, CCI-000225, 4.3.3.7.3, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), AC-6(1), PR.AC-4, PR.DS-5, Req-7.1, 1.4.2


Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_groupowner_efi_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/efi/EFI/redhat/user.cfg
  stat:
    path: /boot/efi/EFI/redhat/user.cfg
  register: file_exists
  when:
  - '"/boot/efi" in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_groupowner_efi_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure group owner 0 on /boot/efi/EFI/redhat/user.cfg
  file:
    path: /boot/efi/EFI/redhat/user.cfg
    group: '0'
  when:
  - '"/boot/efi" in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_groupowner_efi_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure
# Remediation is applicable only in certain platforms
if [ -f /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chgrp 0 /boot/efi/EFI/redhat/user.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Verify the UEFI Boot Loader grub.cfg User Ownership   [ref]

The file /boot/efi/EFI/redhat/grub.cfg should be owned by the root user to prevent destruction or modification of the file. To properly set the owner of /boot/efi/EFI/redhat/grub.cfg, run the command: 
$ sudo chown root /boot/efi/EFI/redhat/grub.cfg
Rationale:
Only root should be able to modify important boot parameters.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_efi_grub2_cfg
Identifiers and References

References:  12, 13, 14, 15, 16, 18, 3, 5, 5.5.2.2, APO01.06, DSS05.04, DSS05.07, DSS06.02, 3.4.5, CCI-000225, 4.3.3.7.3, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), AC-6(1), PR.AC-4, PR.DS-5, Req-7.1, 1.4.2


Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_owner_efi_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/efi/EFI/redhat/grub.cfg
  stat:
    path: /boot/efi/EFI/redhat/grub.cfg
  register: file_exists
  when:
  - '"/boot/efi" in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_owner_efi_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /boot/efi/EFI/redhat/grub.cfg
  file:
    path: /boot/efi/EFI/redhat/grub.cfg
    owner: '0'
  when:
  - '"/boot/efi" in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_owner_efi_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure
# Remediation is applicable only in certain platforms
if [ -f /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chown 0 /boot/efi/EFI/redhat/grub.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Verify /boot/efi/EFI/redhat/user.cfg User Ownership   [ref]

The file /boot/efi/EFI/redhat/user.cfg should be owned by the root user to prevent reading or modification of the file. To properly set the owner of /boot/efi/EFI/redhat/user.cfg, run the command: 
$ sudo chown root /boot/efi/EFI/redhat/user.cfg
Rationale:
Only root should be able to modify important boot parameters. Also, non-root users who read the boot parameters may be able to identify weaknesses in security upon boot and be able to exploit them.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_efi_user_cfg
Identifiers and References

References:  12, 13, 14, 15, 16, 18, 3, 5, 5.5.2.2, APO01.06, DSS05.04, DSS05.07, DSS06.02, 3.4.5, CCI-000225, 4.3.3.7.3, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), AC-6(1), PR.AC-4, PR.DS-5, Req-7.1, 1.4.2


Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_owner_efi_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/efi/EFI/redhat/user.cfg
  stat:
    path: /boot/efi/EFI/redhat/user.cfg
  register: file_exists
  when:
  - '"/boot/efi" in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_owner_efi_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure owner 0 on /boot/efi/EFI/redhat/user.cfg
  file:
    path: /boot/efi/EFI/redhat/user.cfg
    owner: '0'
  when:
  - '"/boot/efi" in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - CJIS-5.5.2.2
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-7.1
  - configure_strategy
  - file_owner_efi_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure
# Remediation is applicable only in certain platforms
if [ -f /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chown 0 /boot/efi/EFI/redhat/user.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Verify the UEFI Boot Loader grub.cfg Permissions   [ref]

File permissions for /boot/efi/EFI/redhat/grub.cfg should be set to 700. To properly set the permissions of /boot/efi/EFI/redhat/grub.cfg, run the command: 
$ sudo chmod 700 /boot/efi/EFI/redhat/grub.cfg
Rationale:
Proper permissions ensure that only the root user can modify important boot parameters.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_efi_grub2_cfg
Identifiers and References

References:  12, 13, 14, 15, 16, 18, 3, 5, APO01.06, DSS05.04, DSS05.07, DSS06.02, 3.4.5, CCI-000225, 4.3.3.7.3, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), AC-6(1), PR.AC-4, PR.DS-5, 1.4.2


Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_efi_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/efi/EFI/redhat/grub.cfg
  stat:
    path: /boot/efi/EFI/redhat/grub.cfg
  register: file_exists
  when:
  - '"/boot/efi" in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_efi_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-s,g-xwrs,o-xwrt on /boot/efi/EFI/redhat/grub.cfg
  file:
    path: /boot/efi/EFI/redhat/grub.cfg
    mode: u-s,g-xwrs,o-xwrt
  when:
  - '"/boot/efi" in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_efi_grub2_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure
# Remediation is applicable only in certain platforms
if [ -f /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chmod u-s,g-xwrs,o-xwrt /boot/efi/EFI/redhat/grub.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Verify /boot/efi/EFI/redhat/user.cfg Permissions   [ref]

File permissions for /boot/efi/EFI/redhat/user.cfg should be set to 600. To properly set the permissions of /boot/efi/EFI/redhat/user.cfg, run the command: 
$ sudo chmod 600 /boot/efi/EFI/redhat/user.cfg
Rationale:
Proper permissions ensure that only the root user can read or modify important boot parameters.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_efi_user_cfg
Identifiers and References

References:  12, 13, 14, 15, 16, 18, 3, 5, APO01.06, DSS05.04, DSS05.07, DSS06.02, 3.4.5, CCI-000225, 4.3.3.7.3, SR 2.1, SR 5.2, A.10.1.1, A.11.1.4, A.11.1.5, A.11.2.1, A.13.1.1, A.13.1.3, A.13.2.1, A.13.2.3, A.13.2.4, A.14.1.2, A.14.1.3, A.6.1.2, A.7.1.1, A.7.1.2, A.7.3.1, A.8.2.2, A.8.2.3, A.9.1.1, A.9.1.2, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), AC-6(1), PR.AC-4, PR.DS-5, 1.4.2


Complexity:low
Disruption:low
Strategy:configure
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_efi_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Test for existence /boot/efi/EFI/redhat/user.cfg
  stat:
    path: /boot/efi/EFI/redhat/user.cfg
  register: file_exists
  when:
  - '"/boot/efi" in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_efi_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

- name: Ensure permission u-xs,g-xwrs,o-xwrt on /boot/efi/EFI/redhat/user.cfg
  file:
    path: /boot/efi/EFI/redhat/user.cfg
    mode: u-xs,g-xwrs,o-xwrt
  when:
  - '"/boot/efi" in ansible_mounts | map(attribute="mount") | list'
  - '"grub2-common" in ansible_facts.packages'
  - ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  - file_exists.stat is defined and file_exists.stat.exists
  tags:
  - NIST-800-171-3.4.5
  - NIST-800-53-AC-6(1)
  - NIST-800-53-CM-6(a)
  - configure_strategy
  - file_permissions_efi_user_cfg
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed

Complexity:low
Disruption:low
Strategy:configure
# Remediation is applicable only in certain platforms
if [ -f /sys/firmware/efi ] && rpm --quiet -q grub2-common && { [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; }; then

chmod u-xs,g-xwrs,o-xwrt /boot/efi/EFI/redhat/user.cfg

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Set the UEFI Boot Loader Password   [ref]

The grub2 boot loader should have a superuser account and password protection enabled to protect boot-time settings.

Since plaintext passwords are a security risk, generate a hash for the password by running the following command: 
# grub2-setpassword
When prompted, enter the password that was selected.

Warning:  To prevent hard-coded passwords, automatic remediation of this control is not available. Remediation must be automated as a component of machine provisioning, or followed manually as outlined above. Also, do NOT manually add the superuser account and password to the grub.cfg file as the grub2-mkconfig command overwrites this file.
Rationale:
Password protection on the boot loader configuration ensures users with physical access cannot trivially alter important bootloader settings. These include which kernel to use, and whether to enter single-user mode.
Severity: 
high
Rule ID:xccdf_org.ssgproject.content_rule_grub2_uefi_password
Identifiers and References

References:  BP28(R17), 11, 12, 14, 15, 16, 18, 3, 5, DSS05.02, DSS05.04, DSS05.05, DSS05.07, DSS06.03, DSS06.06, 3.4.5, CCI-000213, 164.308(a)(1)(ii)(B), 164.308(a)(7)(i), 164.308(a)(7)(ii)(A), 164.310(a)(1), 164.310(a)(2)(i), 164.310(a)(2)(ii), 164.310(a)(2)(iii), 164.310(b), 164.310(c), 164.310(d)(1), 164.310(d)(2)(iii), 4.3.3.2.2, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, A.6.1.2, A.7.1.1, A.9.1.2, A.9.2.1, A.9.2.3, A.9.4.1, A.9.4.4, A.9.4.5, CM-6(a), PR.AC-4, PR.AC-6, PR.PT-3, FIA_UAU.1, SRG-OS-000080-GPOS-00048, 1.4.1, SV-204440r744098_rule

Group   Configure Syslog   Group contains 2 groups and 6 rules
[ref]   The syslog service has been the default Unix logging mechanism for many years. It has a number of downsides, including inconsistent log format, lack of authentication for received messages, and lack of authentication, encryption, or reliable transport for messages sent over a network. However, due to its long history, syslog is a de facto standard which is supported by almost all Unix applications.

In Red Hat Enterprise Linux 7, rsyslog has replaced ksyslogd as the syslog daemon of choice, and it includes some additional security features such as reliable, connection-oriented (i.e. TCP) transmission of logs, the option to log to database formats, and the encryption of log data en route to a central logging server. This section discusses how to configure rsyslog for best effect, and how to use tools provided with the system to maintain and monitor logs.
Group   systemd-journald   Group contains 3 rules
[ref]   systemd-journald is a system service that collects and stores logging data. It creates and maintains structured, indexed journals based on logging information that is received from a variety of sources. For more information on systemd-journald and additional systemd-journald configuration options, see https://systemd.io/.

Rule   Ensure journald is configured to compress large log files   [ref]

The journald system can compress large log files to avoid fill the system disk.
Rationale:
Log files that are not properly compressed run the risk of growing so large that they fill up the log partition. Valuable logging information could be lost if the log partition becomes full.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_journald_compress
Identifiers and References

References:  4.2.2.2


Complexity:low
Disruption:low
Strategy:restrict
- name: Setting shell-quoted shell-style assignment of 'Compress' to 'yes' in '/etc/systemd/journald.conf'
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/systemd/journald.conf
      create: false
      regexp: ^\s*Compress=
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/systemd/journald.conf
    lineinfile:
      path: /etc/systemd/journald.conf
      create: false
      regexp: ^\s*Compress=
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/systemd/journald.conf
    lineinfile:
      path: /etc/systemd/journald.conf
      create: true
      regexp: ^\s*Compress=
      line: Compress="yes"
      state: present
      insertbefore: ^# Compress
      validate: /usr/bin/bash -n %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - journald_compress
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Complexity:low
Disruption:low
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if [ -e "/etc/systemd/journald.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*Compress\s*=\s*/d" "/etc/systemd/journald.conf"
else
    touch "/etc/systemd/journald.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/systemd/journald.conf"

cp "/etc/systemd/journald.conf" "/etc/systemd/journald.conf.bak"
# Insert before the line matching the regex '^#\s*Compress'.
line_number="$(LC_ALL=C grep -n "^#\s*Compress" "/etc/systemd/journald.conf.bak" | LC_ALL=C sed 's/:.*//g')"
if [ -z "$line_number" ]; then
    # There was no match of '^#\s*Compress', insert at
    # the end of the file.
    printf '%s\n' "Compress='yes'" >> "/etc/systemd/journald.conf"
else
    head -n "$(( line_number - 1 ))" "/etc/systemd/journald.conf.bak" > "/etc/systemd/journald.conf"
    printf '%s\n' "Compress='yes'" >> "/etc/systemd/journald.conf"
    tail -n "+$(( line_number ))" "/etc/systemd/journald.conf.bak" >> "/etc/systemd/journald.conf"
fi
# Clean up after ourselves.
rm "/etc/systemd/journald.conf.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure journald is configured to send logs to rsyslog   [ref]

Data from journald may be stored in volatile memory or persisted locally. Utilities exist to accept remote export of journald logs.
Rationale:
Storing log data on a remote host protects log integrity from local attacks. If an attacker gains root access on the local system, they could tamper with or remove log data that is stored on the local system.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_journald_forward_to_syslog
Identifiers and References

References:  4.2.2.1


Complexity:low
Disruption:low
Strategy:restrict
- name: Setting shell-quoted shell-style assignment of 'ForwardToSyslog' to 'yes'
    in '/etc/systemd/journald.conf'
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/systemd/journald.conf
      create: false
      regexp: ^\s*ForwardToSyslog=
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/systemd/journald.conf
    lineinfile:
      path: /etc/systemd/journald.conf
      create: false
      regexp: ^\s*ForwardToSyslog=
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/systemd/journald.conf
    lineinfile:
      path: /etc/systemd/journald.conf
      create: true
      regexp: ^\s*ForwardToSyslog=
      line: ForwardToSyslog="yes"
      state: present
      insertbefore: ^# ForwardToSyslog
      validate: /usr/bin/bash -n %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - journald_forward_to_syslog
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Complexity:low
Disruption:low
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if [ -e "/etc/systemd/journald.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*ForwardToSyslog\s*=\s*/d" "/etc/systemd/journald.conf"
else
    touch "/etc/systemd/journald.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/systemd/journald.conf"

cp "/etc/systemd/journald.conf" "/etc/systemd/journald.conf.bak"
# Insert before the line matching the regex '^#\s*ForwardToSyslog'.
line_number="$(LC_ALL=C grep -n "^#\s*ForwardToSyslog" "/etc/systemd/journald.conf.bak" | LC_ALL=C sed 's/:.*//g')"
if [ -z "$line_number" ]; then
    # There was no match of '^#\s*ForwardToSyslog', insert at
    # the end of the file.
    printf '%s\n' "ForwardToSyslog='yes'" >> "/etc/systemd/journald.conf"
else
    head -n "$(( line_number - 1 ))" "/etc/systemd/journald.conf.bak" > "/etc/systemd/journald.conf"
    printf '%s\n' "ForwardToSyslog='yes'" >> "/etc/systemd/journald.conf"
    tail -n "+$(( line_number ))" "/etc/systemd/journald.conf.bak" >> "/etc/systemd/journald.conf"
fi
# Clean up after ourselves.
rm "/etc/systemd/journald.conf.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure journald is configured to write log files to persistent disk   [ref]

The journald system may store log files in volatile memory or locally on disk. If the logs are only stored in volatile memory they will we lost upon reboot.
Rationale:
Log files contain valuable data and need to be persistent to aid in possible investigations.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_journald_storage
Identifiers and References

References:  4.2.2.3


Complexity:low
Disruption:low
Strategy:restrict
- name: Setting shell-quoted shell-style assignment of 'Storage' to 'persistent' in
    '/etc/systemd/journald.conf'
  block:

  - name: Check for duplicate values
    lineinfile:
      path: /etc/systemd/journald.conf
      create: false
      regexp: ^\s*Storage=
      state: absent
    check_mode: true
    changed_when: false
    register: dupes

  - name: Deduplicate values from /etc/systemd/journald.conf
    lineinfile:
      path: /etc/systemd/journald.conf
      create: false
      regexp: ^\s*Storage=
      state: absent
    when: dupes.found is defined and dupes.found > 1

  - name: Insert correct line to /etc/systemd/journald.conf
    lineinfile:
      path: /etc/systemd/journald.conf
      create: true
      regexp: ^\s*Storage=
      line: Storage="persistent"
      state: present
      insertbefore: ^# Storage
      validate: /usr/bin/bash -n %s
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - journald_storage
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy

Complexity:low
Disruption:low
Strategy:restrict
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if [ -e "/etc/systemd/journald.conf" ] ; then
    
    LC_ALL=C sed -i "/^\s*Storage\s*=\s*/d" "/etc/systemd/journald.conf"
else
    touch "/etc/systemd/journald.conf"
fi
# make sure file has newline at the end
sed -i -e '$a\' "/etc/systemd/journald.conf"

cp "/etc/systemd/journald.conf" "/etc/systemd/journald.conf.bak"
# Insert before the line matching the regex '^#\s*Storage'.
line_number="$(LC_ALL=C grep -n "^#\s*Storage" "/etc/systemd/journald.conf.bak" | LC_ALL=C sed 's/:.*//g')"
if [ -z "$line_number" ]; then
    # There was no match of '^#\s*Storage', insert at
    # the end of the file.
    printf '%s\n' "Storage='persistent'" >> "/etc/systemd/journald.conf"
else
    head -n "$(( line_number - 1 ))" "/etc/systemd/journald.conf.bak" > "/etc/systemd/journald.conf"
    printf '%s\n' "Storage='persistent'" >> "/etc/systemd/journald.conf"
    tail -n "+$(( line_number ))" "/etc/systemd/journald.conf.bak" >> "/etc/systemd/journald.conf"
fi
# Clean up after ourselves.
rm "/etc/systemd/journald.conf.bak"

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Rsyslog Logs Sent To Remote Host   Group contains 1 rule
[ref]   If system logs are to be useful in detecting malicious activities, it is necessary to send logs to a remote server. An intruder who has compromised the root account on a system may delete the log entries which indicate that the system was attacked before they are seen by an administrator.

However, it is recommended that logs be stored on the local host in addition to being sent to the loghost, especially if rsyslog has been configured to use the UDP protocol to send messages over a network. UDP does not guarantee reliable delivery, and moderately busy sites will lose log messages occasionally, especially in periods of high traffic which may be the result of an attack. In addition, remote rsyslog messages are not authenticated in any way by default, so it is easy for an attacker to introduce spurious messages to the central log server. Also, some problems cause loss of network connectivity, which will prevent the sending of messages to the central server. For all of these reasons, it is better to store log messages both centrally and on each host, so that they can be correlated if necessary.

Rule   Ensure Logs Sent To Remote Host   [ref]

To configure rsyslog to send logs to a remote log server, open /etc/rsyslog.conf and read and understand the last section of the file, which describes the multiple directives necessary to activate remote logging. Along with these other directives, the system can be configured to forward its logs to a particular log server by adding or correcting one of the following lines, substituting logcollector appropriately. The choice of protocol depends on the environment of the system; although TCP and RELP provide more reliable message delivery, they may not be supported in all environments.
To use UDP for log message delivery: 
*.* @logcollector

To use TCP for log message delivery: 
*.* @@logcollector

To use RELP for log message delivery: 
*.* :omrelp:logcollector

There must be a resolvable DNS CNAME or Alias record set to "logcollector" for logs to be sent correctly to the centralized logging utility.
Warning:  It is important to configure queues in case the client is sending log messages to a remote server. If queues are not configured, the system will stop functioning when the connection to the remote server is not available. Please consult Rsyslog documentation for more information about configuration of queues. The example configuration which should go into /etc/rsyslog.conf can look like the following lines: 
$ActionQueueType LinkedList
$ActionQueueFileName queuefilename
$ActionQueueMaxDiskSpace 1g
$ActionQueueSaveOnShutdown on
$ActionResumeRetryCount -1
Rationale:
A log server (loghost) receives syslog messages from one or more systems. This data can be used as an additional log source in the event a system is compromised and its local logs are suspect. Forwarding log messages to a remote loghost also provides system administrators with a centralized place to view the status of multiple hosts within the enterprise.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_rsyslog_remote_loghost
Identifiers and References

References:  BP28(R7), NT28(R43), NT12(R5), 1, 13, 14, 15, 16, 2, 3, 5, 6, APO11.04, APO13.01, BAI03.05, BAI04.04, DSS05.04, DSS05.07, MEA02.01, CCI-000366, CCI-001348, CCI-000136, CCI-001851, 164.308(a)(1)(ii)(D), 164.308(a)(5)(ii)(B), 164.308(a)(5)(ii)(C), 164.308(a)(6)(ii), 164.308(a)(8), 164.310(d)(2)(iii), 164.312(b), 164.314(a)(2)(i)(C), 164.314(a)(2)(iii), 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 7.1, SR 7.2, 0988, 1405, A.12.1.3, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.17.2.1, CIP-003-8 R5.2, CIP-004-6 R3.3, CM-6(a), AU-4(1), AU-9(2), PR.DS-4, PR.PT-1, FAU_GEN.1.1.c, SRG-OS-000479-GPOS-00224, SRG-OS-000480-GPOS-00227, SRG-OS-000342-GPOS-00133, SRG-OS-000032-VMM-000130, 4.2.1.4, SV-204574r603261_rule


Complexity:low
Disruption:low
Strategy:restrict
- name: XCCDF Value rsyslog_remote_loghost_address # promote to variable
  set_fact:
    rsyslog_remote_loghost_address: !!str logcollector
  tags:
    - always

- name: Set rsyslog remote loghost
  lineinfile:
    dest: /etc/rsyslog.conf
    regexp: ^\*\.\*
    line: '*.* @@{{ rsyslog_remote_loghost_address }}'
    create: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - DISA-STIG-RHEL-07-031000
  - NIST-800-53-AU-4(1)
  - NIST-800-53-AU-9(2)
  - NIST-800-53-CM-6(a)
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - restrict_strategy
  - rsyslog_remote_loghost


# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

rsyslog_remote_loghost_address='logcollector'


# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/rsyslog.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^\*\.\*")

# shellcheck disable=SC2059
printf -v formatted_output "%s %s" "$stripped_key" "@@$rsyslog_remote_loghost_address"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^\*\.\*\\>" "/etc/rsyslog.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    "${sed_command[@]}" "s/^\*\.\*\\>.*/$escaped_formatted_output/gi" "/etc/rsyslog.conf"
else
    # \n is precaution for case where file ends without trailing newline
    cce=""
    printf '\n# Per %s: Set %s in %s\n' "$cce" "$formatted_output" "/etc/rsyslog.conf" >> "/etc/rsyslog.conf"
    printf '%s\n' "$formatted_output" >> "/etc/rsyslog.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Ensure rsyslog is Installed   [ref]

Rsyslog is installed by default. The rsyslog package can be installed with the following command: 
 $ sudo yum install rsyslog
Rationale:
The rsyslog package provides the rsyslog daemon, which provides system logging services.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_rsyslog_installed
Identifiers and References

References:  BP28(R5), NT28(R46), 1, 14, 15, 16, 3, 5, 6, APO11.04, BAI03.05, DSS05.04, DSS05.07, MEA02.01, CCI-001311, CCI-001312, CCI-000366, 164.312(a)(2)(ii), 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, CM-6(a), PR.PT-1, FTP_ITC_EXT.1.1, SRG-OS-000479-GPOS-00224, SRG-OS-000051-GPOS-00024, SRG-OS-000480-GPOS-00227, 4.2.1.1


Complexity:low
Disruption:low
Strategy:enable
include install_rsyslog

class install_rsyslog {
  package { 'rsyslog':
    ensure => 'installed',
  }
}

Complexity:low
Disruption:low
Strategy:enable

package --add=rsyslog



[[packages]]
name = "rsyslog"
version = "*"

Complexity:low
Disruption:low
Strategy:enable
- name: Ensure rsyslog is installed
  package:
    name: rsyslog
    state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-53-CM-6(a)
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_rsyslog_installed

Complexity:low
Disruption:low
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if ! rpm -q --quiet "rsyslog" ; then
    yum install -y "rsyslog"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Enable rsyslog Service   [ref]

The rsyslog service provides syslog-style logging by default on Red Hat Enterprise Linux 7. The rsyslog service can be enabled with the following command: 
$ sudo systemctl enable rsyslog.service
Rationale:
The rsyslog service must be running in order to provide logging services, which are essential to system administration.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_rsyslog_enabled
Identifiers and References

References:  BP28(R5), NT28(R46), 1, 12, 13, 14, 15, 16, 2, 3, 5, 6, 7, 8, 9, APO10.01, APO10.03, APO10.04, APO10.05, APO11.04, APO13.01, BAI03.05, BAI04.04, DSS01.03, DSS03.05, DSS05.02, DSS05.04, DSS05.05, DSS05.07, MEA01.01, MEA01.02, MEA01.03, MEA01.04, MEA01.05, MEA02.01, CCI-001311, CCI-001312, CCI-001557, CCI-001851, CCI-000366, 164.312(a)(2)(ii), 4.3.2.6.7, 4.3.3.3.9, 4.3.3.5.8, 4.3.4.4.7, 4.4.2.1, 4.4.2.2, 4.4.2.4, SR 2.10, SR 2.11, SR 2.12, SR 2.8, SR 2.9, SR 6.1, SR 6.2, SR 7.1, SR 7.2, A.12.1.3, A.12.4.1, A.12.4.2, A.12.4.3, A.12.4.4, A.12.7.1, A.14.2.7, A.15.2.1, A.15.2.2, A.17.2.1, CM-6(a), AU-4(1), DE.CM-1, DE.CM-3, DE.CM-7, ID.SC-4, PR.DS-4, PR.PT-1, SRG-OS-000480-GPOS-00227, 4.2.1.2


Complexity:low
Disruption:low
Strategy:enable
include enable_rsyslog

class enable_rsyslog {
  service {'rsyslog':
    enable => true,
    ensure => 'running',
  }
}



[customizations.services]
enabled = ["rsyslog"]

Complexity:low
Disruption:low
Strategy:enable
- name: Enable service rsyslog
  block:

  - name: Gather the package facts
    package_facts:
      manager: auto

  - name: Enable service rsyslog
    service:
      name: rsyslog
      enabled: 'yes'
      state: started
      masked: 'no'
    when:
    - '"rsyslog" in ansible_facts.packages'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-53-AU-4(1)
  - NIST-800-53-CM-6(a)
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_rsyslog_enabled

Complexity:low
Disruption:low
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" unmask 'rsyslog.service'
"$SYSTEMCTL_EXEC" start 'rsyslog.service'
"$SYSTEMCTL_EXEC" enable 'rsyslog.service'

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Network Configuration and Firewalls   Group contains 11 groups and 28 rules
[ref]   Most systems must be connected to a network of some sort, and this brings with it the substantial risk of network attack. This section discusses the security impact of decisions about networking which must be made when configuring a system.

This section also discusses firewalls, network access controls, and other network security frameworks, which allow system-level rules to be written that can limit an attackers' ability to connect to your system. These rules can specify that network traffic should be allowed or denied from certain IP addresses, hosts, and networks. The rules can also specify which of the system's network services are available to particular hosts or networks.
Group   firewalld   Group contains 2 groups and 3 rules
[ref]   The dynamic firewall daemon firewalld provides a dynamically managed firewall with support for network “zones” to assign a level of trust to a network and its associated connections and interfaces. It has support for IPv4 and IPv6 firewall settings. It supports Ethernet bridges and has a separation of runtime and permanent configuration options. It also has an interface for services or applications to add firewall rules directly.
A graphical configuration tool, firewall-config, is used to configure firewalld, which in turn uses iptables tool to communicate with Netfilter in the kernel which implements packet filtering.
The firewall service provided by firewalld is dynamic rather than static because changes to the configuration can be made at anytime and are immediately implemented. There is no need to save or apply the changes. No unintended disruption of existing network connections occurs as no part of the firewall has to be reloaded.
Group   Inspect and Activate Default firewalld Rules   Group contains 2 rules
[ref]   Firewalls can be used to separate networks into different zones based on the level of trust the user has decided to place on the devices and traffic within that network. NetworkManager informs firewalld to which zone an interface belongs. An interface's assigned zone can be changed by NetworkManager or via the firewall-config tool.
The zone settings in /etc/firewalld/ are a range of preset settings which can be quickly applied to a network interface. These are the zones provided by firewalld sorted according to the default trust level of the zones from untrusted to trusted:
  • drop

    Any incoming network packets are dropped, there is no reply. Only outgoing network connections are possible.

  • block

    Any incoming network connections are rejected with an icmp-host-prohibited message for IPv4 and icmp6-adm-prohibited for IPv6. Only network connections initiated from within the system are possible.

  • public

    For use in public areas. You do not trust the other computers on the network to not harm your computer. Only selected incoming connections are accepted.

  • external

    For use on external networks with masquerading enabled especially for routers. You do not trust the other computers on the network to not harm your computer. Only selected incoming connections are accepted.

  • dmz

    For computers in your demilitarized zone that are publicly-accessible with limited access to your internal network. Only selected incoming connections are accepted.

  • work

    For use in work areas. You mostly trust the other computers on networks to not harm your computer. Only selected incoming connections are accepted.

  • home

    For use in home areas. You mostly trust the other computers on networks to not harm your computer. Only selected incoming connections are accepted.

  • internal

    For use on internal networks. You mostly trust the other computers on the networks to not harm your computer. Only selected incoming connections are accepted.

  • trusted

    All network connections are accepted.


It is possible to designate one of these zones to be the default zone. When interface connections are added to NetworkManager, they are assigned to the default zone. On installation, the default zone in firewalld is set to be the public zone.
To find out all the settings of a zone, for example the public zone, enter the following command as root: 
# firewall-cmd --zone=public --list-all
Example output of this command might look like the following: 
# firewall-cmd --zone=public --list-all
public
  interfaces:
  services: mdns dhcpv6-client ssh
  ports:
  forward-ports:
  icmp-blocks: source-quench
To view the network zones currently active, enter the following command as root: 
# firewall-cmd --get-service
The following listing displays the result of this command on common Red Hat Enterprise Linux 7 system: 
# firewall-cmd --get-service
amanda-client bacula bacula-client dhcp dhcpv6 dhcpv6-client dns ftp
high-availability http https imaps ipp ipp-client ipsec kerberos kpasswd
ldap ldaps libvirt libvirt-tls mdns mountd ms-wbt mysql nfs ntp openvpn
pmcd pmproxy pmwebapi pmwebapis pop3s postgresql proxy-dhcp radius rpc-bind
samba samba-client smtp ssh telnet tftp tftp-client transmission-client
vnc-server wbem-https
Finally to view the network zones that will be active after the next firewalld service reload, enter the following command as root: 
# firewall-cmd --get-service --permanent

Rule   Install firewalld Package   [ref]

The firewalld package can be installed with the following command: 
$ sudo yum install firewalld
Rationale:
"Firewalld" provides an easy and effective way to block/limit remote access to the system via ports, services, and protocols. Remote access services, such as those providing remote access to network devices and information systems, which lack automated control capabilities, increase risk and make remote user access management difficult at best. Remote access is access to DoD nonpublic information systems by an authorized user (or an information system) communicating through an external, non-organization-controlled network. Remote access methods include, for example, dial-up, broadband, and wireless. Red Hat Enterprise Linux 7 functionality (e.g., SSH) must be capable of taking enforcement action if the audit reveals unauthorized activity. Automated control of remote access sessions allows organizations to ensure ongoing compliance with remote access policies by enforcing connection rules of remote access applications on a variety of information system components (e.g., servers, workstations, notebook computers, smartphones, and tablets)."
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_firewalld_installed
Identifiers and References

References:  CCI-002314, CM-6(a), FMT_SMF_EXT.1, SRG-OS-000096-GPOS-00050, SRG-OS-000297-GPOS-00115, SRG-OS-000298-GPOS-00116, SRG-OS-000480-GPOS-00227, SRG-OS-000480-GPOS-00232, 3.5.1.1


Complexity:low
Disruption:low
Strategy:enable
include install_firewalld

class install_firewalld {
  package { 'firewalld':
    ensure => 'installed',
  }
}

Complexity:low
Disruption:low
Strategy:enable

package --add=firewalld



[[packages]]
name = "firewalld"
version = "*"

Complexity:low
Disruption:low
Strategy:enable
- name: Ensure firewalld is installed
  package:
    name: firewalld
    state: present
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-53-CM-6(a)
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_firewalld_installed

Complexity:low
Disruption:low
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

if ! rpm -q --quiet "firewalld" ; then
    yum install -y "firewalld"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Verify firewalld Enabled   [ref]

The firewalld service can be enabled with the following command: 
$ sudo systemctl enable firewalld.service
Rationale:
Access control methods provide the ability to enhance system security posture by restricting services and known good IP addresses and address ranges. This prevents connections from unknown hosts and protocols.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_service_firewalld_enabled
Identifiers and References

References:  11, 3, 9, BAI10.01, BAI10.02, BAI10.03, BAI10.05, 3.1.3, 3.4.7, CCI-000366, CCI-000382, CCI-002314, 4.3.4.3.2, 4.3.4.3.3, SR 7.6, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, CIP-003-8 R4, CIP-003-8 R5, CIP-004-6 R3, AC-4, CM-7(b), CA-3(5), SC-7(21), CM-6(a), PR.IP-1, FMT_SMF_EXT.1, SRG-OS-000096-GPOS-00050, SRG-OS-000297-GPOS-00115, SRG-OS-000480-GPOS-00227, SRG-OS-000480-GPOS-00231, SRG-OS-000480-GPOS-00232, 3.5.1.4, SV-204604r603261_rule


Complexity:low
Disruption:low
Strategy:enable
include enable_firewalld

class enable_firewalld {
  service {'firewalld':
    enable => true,
    ensure => 'running',
  }
}



[customizations.services]
enabled = ["firewalld"]

Complexity:low
Disruption:low
Strategy:enable
- name: Enable service firewalld
  block:

  - name: Gather the package facts
    package_facts:
      manager: auto

  - name: Enable service firewalld
    service:
      name: firewalld
      enabled: 'yes'
      state: started
      masked: 'no'
    when:
    - '"firewalld" in ansible_facts.packages'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - DISA-STIG-RHEL-07-040520
  - NIST-800-171-3.1.3
  - NIST-800-171-3.4.7
  - NIST-800-53-AC-4
  - NIST-800-53-CA-3(5)
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(b)
  - NIST-800-53-SC-7(21)
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - service_firewalld_enabled

Complexity:low
Disruption:low
Strategy:enable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" unmask 'firewalld.service'
"$SYSTEMCTL_EXEC" start 'firewalld.service'
"$SYSTEMCTL_EXEC" enable 'firewalld.service'

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
Group   Strengthen the Default Ruleset   Group contains 1 rule
[ref]   The default rules can be strengthened. The system scripts that activate the firewall rules expect them to be defined in configuration files under the /etc/firewalld/services and /etc/firewalld/zones directories.

The following recommendations describe how to strengthen the default ruleset configuration file. An alternative to editing this configuration file is to create a shell script that makes calls to the firewall-cmd program to load in rules under the /etc/firewalld/services and /etc/firewalld/zones directories.

Instructions apply to both unless otherwise noted. Language and address conventions for regular firewalld rules are used throughout this section.
Warning:  The program firewall-config allows additional services to penetrate the default firewall rules and automatically adjusts the firewalld ruleset(s).

Rule   Set Default firewalld Zone for Incoming Packets   [ref]

To set the default zone to drop for the built-in default zone which processes incoming IPv4 and IPv6 packets, modify the following line in /etc/firewalld/firewalld.conf to be: 
DefaultZone=drop
Warning:  To prevent denying any access to the system, automatic remediation of this control is not available. Remediation must be automated as a component of machine provisioning, or followed manually as outlined above.
Rationale:
In firewalld the default zone is applied only after all the applicable rules in the table are examined for a match. Setting the default zone to drop implements proper design for a firewall, i.e. any packets which are not explicitly permitted should not be accepted.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_set_firewalld_default_zone
Identifiers and References

References:  11, 14, 3, 9, 5.10.1, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06, 3.1.3, 3.4.7, 3.13.6, CCI-000366, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 7.6, 1416, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.9.1.2, CA-3(5), CM-7(b), SC-7(23), CM-6(a), PR.IP-1, PR.PT-3, FMT_MOF_EXT.1, Req-1.4, SRG-OS-000480-GPOS-00227, SRG-OS-000480-VMM-002000, 3.5.1.5, SV-204628r603261_rule

Group   iptables and ip6tables   Group contains 1 rule
[ref]   A host-based firewall called netfilter is included as part of the Linux kernel distributed with the system. It is activated by default. This firewall is controlled by the program iptables, and the entire capability is frequently referred to by this name. An analogous program called ip6tables handles filtering for IPv6.

Unlike TCP Wrappers, which depends on the network server program to support and respect the rules written, netfilter filtering occurs at the kernel level, before a program can even process the data from the network packet. As such, any program on the system is affected by the rules written.

This section provides basic information about strengthening the iptables and ip6tables configurations included with the system. For more complete information that may allow the construction of a sophisticated ruleset tailored to your environment, please consult the references at the end of this section.

Rule   Install iptables Package   [ref]

The iptables package can be installed with the following command: 
$ sudo yum install iptables
Rationale:
iptables controls the Linux kernel network packet filtering code. iptables allows system operators to set up firewalls and IP masquerading, etc.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_package_iptables_installed
Identifiers and References

References:  CM-6(a), Req-1.4.1, SRG-OS-000480-GPOS-00227, 3.5.1.1, 3.5.3.1.1


Complexity:low
Disruption:low
Strategy:enable
include install_iptables

class install_iptables {
  package { 'iptables':
    ensure => 'installed',
  }
}

Complexity:low
Disruption:low
Strategy:enable

package --add=iptables



[[packages]]
name = "iptables"
version = "*"

Complexity:low
Disruption:low
Strategy:enable
- name: Ensure iptables is installed
  package:
    name: iptables
    state: present
  tags:
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-1.4.1
  - enable_strategy
  - low_complexity
  - low_disruption
  - medium_severity
  - no_reboot_needed
  - package_iptables_installed

Complexity:low
Disruption:low
Strategy:enable

if ! rpm -q --quiet "iptables" ; then
    yum install -y "iptables"
fi
Group   IPv6   Group contains 1 group and 7 rules
[ref]   The system includes support for Internet Protocol version 6. A major and often-mentioned improvement over IPv4 is its enormous increase in the number of available addresses. Another important feature is its support for automatic configuration of many network settings.
Group   Configure IPv6 Settings if Necessary   Group contains 7 rules
[ref]   A major feature of IPv6 is the extent to which systems implementing it can automatically configure their networking devices using information from the network. From a security perspective, manually configuring important configuration information is preferable to accepting it from the network in an unauthenticated fashion.

Rule   Configure Accepting Router Advertisements on All IPv6 Interfaces   [ref]

To set the runtime status of the net.ipv6.conf.all.accept_ra kernel parameter, run the following command: 
$ sudo sysctl -w net.ipv6.conf.all.accept_ra=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d: 
net.ipv6.conf.all.accept_ra = 0
Rationale:
An illicit router advertisement message could result in a man-in-the-middle attack.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_all_accept_ra
Identifiers and References

References:  11, 14, 3, 9, BAI10.01, BAI10.02, BAI10.03, BAI10.05, DSS05.02, DSS05.05, DSS06.06, 3.1.20, CCI-000366, 4.3.3.5.1, 4.3.3.5.2, 4.3.3.5.3, 4.3.3.5.4, 4.3.3.5.5, 4.3.3.5.6, 4.3.3.5.7, 4.3.3.5.8, 4.3.3.6.1, 4.3.3.6.2, 4.3.3.6.3, 4.3.3.6.4, 4.3.3.6.5, 4.3.3.6.6, 4.3.3.6.7, 4.3.3.6.8, 4.3.3.6.9, 4.3.3.7.1, 4.3.3.7.2, 4.3.3.7.3, 4.3.3.7.4, 4.3.4.3.2, 4.3.4.3.3, SR 1.1, SR 1.10, SR 1.11, SR 1.12, SR 1.13, SR 1.2, SR 1.3, SR 1.4, SR 1.5, SR 1.6, SR 1.7, SR 1.8, SR 1.9, SR 2.1, SR 2.2, SR 2.3, SR 2.4, SR 2.5, SR 2.6, SR 2.7, SR 7.6, A.12.1.2, A.12.5.1, A.12.6.2, A.14.2.2, A.14.2.3, A.14.2.4, A.9.1.2, CM-7(a), CM-7(b), CM-6(a), PR.IP-1, PR.PT-3, SRG-OS-000480-GPOS-00227, 3.3.9


---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:,net.ipv6.conf.all.accept_ra%3D0%0A
        mode: 0644
        path: /etc/sysctl.d/75-sysctl_net_ipv6_conf_all_accept_ra.conf
        overwrite: true

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
- name: List /etc/sysctl.d/*.conf files
  find:
    paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
    contains: ^[\s]*net.ipv6.conf.all.accept_ra.*$
    patterns: '*.conf'
    file_type: any
  register: find_sysctl_d
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_ra

- name: Comment out any occurrences of net.ipv6.conf.all.accept_ra from config files
  replace:
    path: '{{ item.path }}'
    regexp: ^[\s]*net.ipv6.conf.all.accept_ra
    replace: '#net.ipv6.conf.all.accept_ra'
  loop: '{{ find_sysctl_d.files }}'
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_ra
- name: XCCDF Value sysctl_net_ipv6_conf_all_accept_ra_value # promote to variable
  set_fact:
    sysctl_net_ipv6_conf_all_accept_ra_value: !!str 0
  tags:
    - always

- name: Ensure sysctl net.ipv6.conf.all.accept_ra is set
  sysctl:
    name: net.ipv6.conf.all.accept_ra
    value: '{{ sysctl_net_ipv6_conf_all_accept_ra_value }}'
    state: present
    reload: true
  when: ansible_virtualization_type not in ["docker", "lxc", "openvz", "podman", "container"]
  tags:
  - NIST-800-171-3.1.20
  - NIST-800-53-CM-6(a)
  - NIST-800-53-CM-7(a)
  - NIST-800-53-CM-7(b)
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_net_ipv6_conf_all_accept_ra

Complexity:low
Disruption:medium
Reboot:true
Strategy:disable
# Remediation is applicable only in certain platforms
if [ ! -f /.dockerenv ] && [ ! -f /run/.containerenv ]; then

# Comment out any occurrences of net.ipv6.conf.all.accept_ra from /etc/sysctl.d/*.conf files

for f in /etc/sysctl.d/*.conf /run/sysctl.d/*.conf /usr/local/lib/sysctl.d/*.conf; do

  matching_list=$(grep -P '^(?!#).*[\s]*net.ipv6.conf.all.accept_ra.*$' $f | uniq )
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "net.ipv6.conf.all.accept_ra" matches to preserve user data
      sed -i "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done
sysctl_net_ipv6_conf_all_accept_ra_value='0'


#
# Set runtime for net.ipv6.conf.all.accept_ra
#
/sbin/sysctl -q -n -w net.ipv6.conf.all.accept_ra="$sysctl_net_ipv6_conf_all_accept_ra_value"

#
# If net.ipv6.conf.all.accept_ra present in /etc/sysctl.conf, change value to appropriate value
#	else, add "net.ipv6.conf.all.accept_ra = value" to /etc/sysctl.conf
#
# Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
# Otherwise, regular sed command will do.
sed_command=('sed' '-i')
if test -L "/etc/sysctl.conf"; then
    sed_command+=('--follow-symlinks')
fi

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^net.ipv6.conf.all.accept_ra")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "$sysctl_net_ipv6_conf_all_accept_ra_value"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^net.ipv6.conf.all.accept_ra\\>" "/etc/sysctl.conf"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    "${sed_command[@]}" "s/^net.ipv6.conf.all.accept_ra\\>.*/$escaped_formatted_output/gi" "/etc/sysctl.conf"
else
    # \n is precaution for case where file ends without trailing newline
    cce=""
    printf '\n# Per %s: Set %s in %s\n' "$cce" "$formatted_output" "/etc/sysctl.conf" >> "/etc/sysctl.conf"
    printf '%s\n' "$formatted_output" >> "/etc/sysctl.conf"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Rule   Disable Accepting ICMP Redirects for All IPv6 Interfaces   [ref]

To set the runtime status of the net.ipv6.conf.all.accept_redirects kernel parameter, run the following command: 
$ sudo sysctl -w net.ipv6.conf.all.accept_redirects=0
To make sure that the setting is persistent, add the following li