Title

Kubernetes Kubelet must deny hostname override. (Cat II impact)

Discussion

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.

Check Content

On the Master and each Worker node, change to the /etc/sysconfig/ directory and run the command: grep -i hostname-override kubelet --hostname-override If any of the nodes have the setting "hostname-override" present, this is a finding.

Fix Text

Edit the Kubernetes Kubelet file in the /etc/sysconfig directory on the Master and Worker nodes and remove the "--hostname-override" setting. Restart the service after the change is made by running: service kubelet restart

Additional Identifiers

Rule ID: SV-242404r712568_rule

Vulnerability ID: V-242404

Group Title: SRG-APP-000133-CTR-000290

Expert Comments

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