cis-ocp-v180-1-2-21

name	cis-ocp-v180-1.2.21
description	Configure Kubernetes API Server Maximum Audit Log Size (Manual)
category	cis-openshift
version	1.8.0
author	cyberstrike-official
tags	["cis","openshift","kubernetes","redhat","control-plane","api-server"]
cis_id	1.2.21
cis_benchmark	CIS Red Hat OpenShift Container Platform Benchmark v1.8.0
tech_stack	["kubernetes","openshift","redhat"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

CIS Red Hat OpenShift Container Platform Benchmark v1.8.0 - Control 1.2.21

Profile Applicability

• Level: 1

Description

Audit logs are rotated upon reaching a maximum size, which is set to 100 MB or greater by default.

Rationale

OpenShift automatically rotates the log files. Retaining old log files ensures that you would have sufficient log data available for carrying out any investigation or correlation. If you have set file size of 100 MB and the number of old log files to keep as 10, you would have approximately 1 GB of log data that you could potentially use for your analysis.

Impact

Overriding can be done by using unsupportedConfigOverrides, it is NOT supported by Red Hat and will block future OpenShift Container Platform Upgrades.

Audit Procedure

OpenShift audit works at the API server level, logging all requests coming to the server. Configure via audit-log-maxsize.

Run the following command:

oc get configmap config -n openshift-kube-apiserver -ojson | jq -r '.data["config.yaml"]' | jq -r '.apiServerArguments["audit-log-maxsize"][]?'

Verify that the audit-log-maxsize argument is set to 100 or greater.

Remediation

The audit-log-maxsize parameter is set by default by Red Hat and not supported to change.

Default Value

By default, auditing is enabled.

References

1. https://access.redhat.com/solutions/4262201
2. https://docs.openshift.com/container-platform/4.5/nodes/nodes/nodes-nodes-audit-log.html
3. https://docs.openshift.com/container-platform/4.5/operators/operator-reference.html#kube-apiserver-operator_red-hat-operators
4. https://docs.openshift.com/container-platform/4.5/operators/operator-reference.html#openshift-apiserver-operator_red-hat-operators
5. https://kubernetes.io/docs/reference/command-line-tools-reference/kube-apiserver/
6. https://kubernetes.io/docs/tasks/debug-application-cluster/audit/