Kubernetes Kubelet must deny hostname override.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-242404	CNTR-K8-000850	SV-242404r863980_rule		Medium

Description
Kubernetes allows for the overriding of hostnames. Allowing this feature to be implemented within the kubelets may break the TLS setup between the kubelet service and the API server. This setting also can make it difficult to associate logs with nodes if security analytics needs to take place. The better practice is to setup nodes with resolvable FQDNs and avoid overriding the hostnames.

STIG	Date
Kubernetes Security Technical Implementation Guide	2022-12-02

Details

Check Text ( C-45679r863809_chk )
On the Kubernetes Control Plane and Worker nodes, run the command: ps -ef | grep kubelet Check the config file (path identified by: --config): Change to the directory identified by --config (example /etc/sysconfig/) run the command: grep -i hostname-override kubelet If any of the nodes have the setting "hostname-override" present, this is a finding.

Fix Text (F-45637r863810_fix)
Edit the kubelet file on each node under the --config directory and remove the hostname-override setting. Reset Kubelet service using the following command: service kubelet restart