Cis K8S V1110 4.1.1

4.1.1 Ensure that the kubelet service file permissions are set to 600 or more restrictive (Automated)

Profile Applicability

• Level 1 - Master Node

Description

Ensure that the kubelet service file has permissions of 600 or more restrictive.

Rationale

The kubelet service file controls various parameters that set the behavior of the kubelet service in the worker node. You should restrict its file permissions to maintain the integrity of the file. The file should be writable by only the administrators on the system.

Impact

None

Audit

Automated AAC auditing has been modified to allow CIS-CAT to input a variable for the <PATH>/<FILENAME> of the kubelet service config file. Please set $kubelet_service_config=<PATH> based on the file location on your system for example:

export kubelet_service_config=/etc/systemd/system/kubelet.service.d/kubeadm.conf

To perform the audit manually: Run the below command (based on the file location on your system) on the each worker node. For example,

stat -c %a /etc/systemd/system/kubelet.service.d/10-kubeadm.conf

Verify that the permissions are 600 or more restrictive.

Remediation

Run the below command (based on the file location on your system) on the each worker node. For example,

chmod 600 /etc/systemd/system/kubelet.service.d/kubeadm.conf

Default Value

By default, the kubelet service file has permissions of 640.

References

1. https://kubernetes.io/docs/admin/kubelet/
2. https://kubernetes.io/docs/setup/independent/create-cluster-kubeadm/#44-joining-your-nodes
3. https://kubernetes.io/docs/admin/kubeadm/#kubelet-drop-in

CIS Controls