cis-k8s-v1120-4-1-7

name	cis-k8s-v1120-4.1.7
description	Ensure that the certificate authorities file permissions are set to 644 or more restrictive (Manual)
category	cis-k8s
version	1.12.0
author	cyberstrike-official
tags	["cis","kubernetes","worker-nodes","worker-node-config","file-permissions"]
cis_id	4.1.7
cis_benchmark	CIS Kubernetes Benchmark v1.12.0
tech_stack	["kubernetes"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

CIS Kubernetes Benchmark v1.12.0 - Control 4.1.7

Description

Ensure that the certificate authorities file has permissions of 644 or more restrictive.

Rationale

The certificate authorities file controls the authorities used to validate API requests. You should restrict its file permissions to maintain the integrity of the file. The file should be writable by only the administrators on the system.

Impact

None

Audit Procedure

Step 1: Find the client-ca-file

Run the following command:

ps -ef | grep kubelet

Find the file specified by the --client-ca-file argument.

Step 2: Verify file permissions

Run the following command:

stat -c %a <filename>

Verify that the permissions are 644 or more restrictive.

Remediation

Run the following command to modify the file permissions of the --client-ca-file:

chmod 644 <filename>

Default Value

By default no --client-ca-file is specified.

References

1. https://kubernetes.io/docs/admin/authentication/#x509-client-certs

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v8	3.3 Configure Data Access Control Lists Configure data access control lists based on a user's need to know. Apply data access control lists, also known as access permissions, to local and remote file systems, databases, and applications.	●	●	●
v7	14.6 Protect Information through Access Control Lists Protect all information stored on systems with file system, network share, claims, application, or database specific access control lists.	●	●	●

Profile Applicability

• Level 1 - Worker Node

Assessment Status

Manual