Ensure that the --rotate-certificates argument is not present or is set to true (Kubelet)
Enable kubelet client certificate rotation. The --rotate-certificates setting causes the kubelet to rotate its client certificates by creating new CSRs 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.
Risk Level: High
Cloud Entity: Node
CloudGuard Rule ID: D9.K8S.CRY.46
Covered by Spectral: No
Category: Compute
GSL LOGIC
KubernetesNode where kubeletData.kubeletconfig.rotateCertificates should have 'true'
REMEDIATION
-If modifying the Kubelet config file, edit the kubelet-config.json file
/etc/kubernetes/kubelet/kubelet-config.json and set the below parameter to true
'RotateCertificate':true
Additionally, ensure that the kubelet service file
/etc/systemd/system/kubelet.service.d/10-kubelet-args.conf does not set the --
RotateCertificate executable argument to false because this would override the Kubelet
config file.
-If using executable arguments, edit the kubelet service file
/etc/systemd/system/kubelet.service.d/10-kubelet-args.conf on each worker node
and add the below parameter at the end of the KUBELET_ARGS variable string.
--RotateCertificate=true
References
- https://github.com/kubernetes/kubernetes/pull/41912
- https://kubernetes.io/docs/reference/command-line-tools-reference/kubelet-tls-bootstrapping/#kubelet-configuration
- https://kubernetes.io/docs/reference/command-line-tools-reference/feature-gates/
- https://kubernetes.io/docs/tasks/administer-cluster/reconfigure-kubelet/ (EKS)
Node
A node is a worker machine in Kubernetes, previously known as a minion. A node may be a VM or physical machine, depending on the cluster. Each node contains the services necessary to run pods and is managed by the master components. The services on a node include the container runtime, kubelet and kube-proxy.
Compliance Frameworks
- TBD
Updated about 1 year ago