C-0149 - Ensure that the Controller Manager RotateKubeletServerCertificate argument is set to true
Framework
cis-v1.23-t1.0.1
Severity
Medium
Description of the the issue
RotateKubeletServerCertificate
causes the kubelet to both request a serving certificate after bootstrapping its client credentials and rotate the certificate as its existing credentials expire. This automated periodic rotation ensures that the there are no downtimes due to expired certificates and thus addressing availability in the CIA security triad.
Note: This recommendation only applies if you let kubelets get their certificates from the API server. In case your kubelet certificates come from an outside authority/tool (e.g. Vault) then you need to take care of rotation yourself.
Related resources
Pod
What does this control test
Enable kubelet server certificate rotation on controller-manager.
How to check it manually
Run the following command on the Control Plane node:
ps -ef | grep kube-controller-manager
Verify that RotateKubeletServerCertificate
argument exists and is set to true
.
Remediation
Edit the Controller Manager pod specification file /etc/kubernetes/manifests/kube-controller-manager.yaml
on the Control Plane node and set the --feature-gates
parameter to include RotateKubeletServerCertificate=true
.
--feature-gates=RotateKubeletServerCertificate=true
Impact Statement
None
Default Value
By default, RotateKubeletServerCertificate
is set to "true" this recommendation verifies that it has not been disabled.
Example
No example
Updated 3 months ago