The Kubernetes Kubelet certificate authority file must have file permissions set to 644 or more restrictive.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-242449	CNTR-K8-003160	SV-242449r712703_rule		Medium

Description
The Kubernetes kubelet certificate authority file contains settings for the Kubernetes Node TLS certificate authority. Any request presenting a client certificate signed by one of the authorities in the client-ca-file is authenticated with an identity corresponding to the CommonName of the client certificate. If this file can be changed, the Kubernetes architecture could be compromised. The scheduler will implement the changes immediately. Many of the security settings within the document are implemented through this file.

Description

The Kubernetes kubelet certificate authority file contains settings for the Kubernetes Node TLS certificate authority. Any request presenting a client certificate signed by one of the authorities in the client-ca-file is authenticated with an identity corresponding to the CommonName of the client certificate. If this file can be changed, the Kubernetes architecture could be compromised. The scheduler will implement the changes immediately. Many of the security settings within the document are implemented through this file.

STIG	Date
Kubernetes Security Technical Implementation Guide	2021-04-14

Details

Check Text ( C-45724r712701_chk )
Change to the /etc/sysconfig/ directory on the Kubernetes Master Node. Run command: more kubelet --client-ca-file argument Note certificate location If the ca-file argument location file has permissions more permissive than "644", this is a finding.

Fix Text (F-45682r712702_fix)
Change the permissions of the --client-ca-file to "644" by executing the command: chown 644 .