Guide to the Secure Configuration of Amazon Elastic Kubernetes Service

with profile CIS Amazon Elastic Kubernetes Service (EKS) Benchmark - Node
This profile defines a baseline that aligns to the Center for Internet Security® Amazon Elastic Kubernetes Service (EKS) Benchmark™, V1.0.1. This profile includes Center for Internet Security® Amazon Elastic Kubernetes Service (EKS)™ content. This profile is applicable to EKS 1.21 and greater.
This guide presents a catalog of security-relevant configuration settings for Amazon Elastic Kubernetes Service. 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 NIST National Checklist Program (NCP), which provides required settings for the United States Government, is one example of a baseline created from this guidance.
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 Amazon Elastic Kubernetes Service (EKS) Benchmark - Node
Profile IDxccdf_org.ssgproject.content_profile_cis-node

CPE Platforms

  • cpe:/a:amazon:elastic_kubernetes_service:1
  • cpe:/o:amazon:elastic_kubernetes_service_node:1
  • cpe:/a:amazon:elastic_kubernetes_service_node:1.21

Revision History

Current version: 0.1.64

  • draft (as of 2022-09-30)

Table of Contents

  1. Kubernetes Settings
    1. Kubernetes Kubelet Settings
    2. Kubernetes - Worker Node Settings

Checklist

Group   Guide to the Secure Configuration of Amazon Elastic Kubernetes Service   Group contains 3 groups and 7 rules
Group   Kubernetes Settings   Group contains 2 groups and 7 rules
[ref]   Each section of this configuration guide includes information about the configuration of a Kubernetes cluster and a set of recommendations for hardening the configuration. For each hardening recommendation, information on how to implement the control and/or how to verify or audit the control is provided. In some cases, remediation information is also provided. Some of the settings in the hardening guide are in place by default. The audit information for these settings is provided in order to verify that the cluster admininstrator has not made changes that would be less secure. A small number of items require configuration. Finally, there are some recommendations that require decisions by the system operator, such as audit log size, retention, and related settings.
Group   Kubernetes Kubelet Settings   Group contains 1 rule
[ref]   The Kubernetes Kubelet is an agent that runs on each node in the cluster. It makes sure that containers are running in a pod. The kubelet takes a set of PodSpecs that are provided through various mechanisms and ensures that the containers described in those PodSpecs are running and healthy. The kubelet doesn’t manage containers which were not created by Kubernetes.

Rule   kubelet - Enable Protect Kernel Defaults   [ref]

Protect tuned kernel parameters from being overwritten by the kubelet.

Rationale:
Kernel parameters are usually tuned and hardened by the system administrators before putting the systems into production. These parameters protect the kernel and the system. Your kubelet kernel defaults that rely on such parameters should be appropriately set to match the desired secured system state. Ignoring this could potentially lead to running pods with undesired kernel behavior.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_kubelet_enable_protect_kernel_defaults
Identifiers and References

References:  CIP-003-8 R6, CIP-004-6 R3, CIP-007-3 R6.1, CM-6, CM-6(1), SRG-APP-000516-CTR-001325, SRG-APP-000516-CTR-001330, SRG-APP-000516-CTR-001335, 3.2.6

Group   Kubernetes - Worker Node Settings   Group contains 6 rules
[ref]   Contains evaluations for the worker node configuration settings.

Rule   Verify Group Who Owns The Kubelet Configuration File   [ref]

To properly set the group owner of /etc/kubernetes/kubelet/kubelet-config.json, run the command:
$ sudo chgrp root /etc/kubernetes/kubelet/kubelet-config.json
Rationale:
The kubelet configuration file contains information about the configuration of the OpenShift node that is configured on the system. Protection of this file is critical for OpenShift security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_kubelet_conf
Identifiers and References

References:  CIP-003-8 R6, CIP-004-6 R3, CIP-007-3 R6.1, CM-6, CM-6(1), SRG-APP-000516-CTR-001325, SRG-APP-000516-CTR-001330, SRG-APP-000516-CTR-001335, 3.1.4

Rule   Verify Group Who Owns The Worker Kubeconfig File   [ref]

To properly set the group owner of /var/lib/kubelet/kubeconfig, run the command:
$ sudo chgrp root /var/lib/kubelet/kubeconfig
Rationale:
The worker kubeconfig file contains information about the administrative configuration of the OpenShift cluster that is configured on the system. Protection of this file is critical for OpenShift security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_groupowner_worker_kubeconfig
Identifiers and References

References:  CIP-003-8 R6, CIP-004-6 R3, CIP-007-3 R6.1, CM-6, CM-6(1), SRG-APP-000516-CTR-001325, SRG-APP-000516-CTR-001330, SRG-APP-000516-CTR-001335

Rule   Verify User Who Owns The Kubelet Configuration File   [ref]

To properly set the owner of /etc/kubernetes/kubelet/kubelet-config.json, run the command:
$ sudo chown root /etc/kubernetes/kubelet/kubelet-config.json 
Rationale:
The kubelet configuration file contains information about the configuration of the OpenShift node that is configured on the system. Protection of this file is critical for OpenShift security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_kubelet_conf
Identifiers and References

References:  CIP-003-8 R6, CIP-004-6 R3, CIP-007-3 R6.1, CM-6, CM-6(1), SRG-APP-000516-CTR-001325, SRG-APP-000516-CTR-001330, SRG-APP-000516-CTR-001335, 3.1.4

Rule   Verify User Who Owns The Worker Kubeconfig File   [ref]

To properly set the owner of /var/lib/kubelet/kubeconfig, run the command:
$ sudo chown root /var/lib/kubelet/kubeconfig 
Rationale:
The worker kubeconfig file contains information about the administrative configuration of the OpenShift cluster that is configured on the system. Protection of this file is critical for OpenShift security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_owner_worker_kubeconfig
Identifiers and References

References:  CIP-003-8 R6, CIP-004-6 R3, CIP-007-3 R6.1, CM-6, CM-6(1), SRG-APP-000516-CTR-001325, SRG-APP-000516-CTR-001330, SRG-APP-000516-CTR-001335, 3.1.2

Rule   Verify Permissions on The Kubelet Configuration File   [ref]

To properly set the permissions of /etc/kubernetes/kubelet/kubelet-config.json, run the command:
$ sudo chmod 0644 /etc/kubernetes/kubelet/kubelet-config.json
Rationale:
If the kubelet configuration file is writable by a group-owner or the world the risk of its compromise is increased. The file contains the configuration of an OpenShift node that is configured on the system. Protection of this file is critical for OpenShift security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_kubelet_conf
Identifiers and References

References:  CIP-003-8 R6, CIP-004-6 R3, CIP-007-3 R6.1, CM-6, CM-6(1), SRG-APP-000516-CTR-001325, SRG-APP-000516-CTR-001330, SRG-APP-000516-CTR-001335, 3.1.3

Rule   Verify Permissions on the Worker Kubeconfig File   [ref]

To properly set the permissions of /var/lib/kubelet/kubeconfig, run the command:
$ sudo chmod 0644 /var/lib/kubelet/kubeconfig
Rationale:
If the worker kubeconfig file is writable by a group-owner or the world the risk of its compromise is increased. The file contains the administration configuration of the OpenShift cluster that is configured on the system. Protection of this file is critical for OpenShift security.
Severity: 
medium
Rule ID:xccdf_org.ssgproject.content_rule_file_permissions_worker_kubeconfig
Identifiers and References

References:  CIP-003-8 R6, CIP-004-6 R3, CIP-007-3 R6.1, CM-6, CM-6(1), SRG-APP-000516-CTR-001325, SRG-APP-000516-CTR-001330, SRG-APP-000516-CTR-001335, 3.1.1

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