The kubelet configuration file should have permissions of 644 or more restrictive
Set up the kubernetes integration.
Description
Ensure that if the kubelet refers to a configuration file with the --config argument, that file has permissions of 644 or more restrictive.
Rationale
The kubelet reads various parameters, including security settings, from a config file specified by the --config argument. If this file is specified 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.
Audit
Locate the Kubelet config file as follows: ps -ef | grep kubelet | grep config. If the --config argument is present, this gives the location of the Kubelet config file, for example /var/lib/kubelet/config.yaml. Run the following command (using the file location you just identified) to find that file’s permissions: stat -c %a /var/lib/kubelet/config.yaml. Verify that the permissions are 644 or more restrictive.
Run the following command (using the config file location identified in the Audit step:
chmod 644 /var/lib/kubelet/config.yaml
Impact
None
Default value
By default, the /var/lib/kubelet/config.yaml file as set up by kubeadm has permissions of 644.
References
- https://kubernetes.io/docs/tasks/administer-cluster/kubelet-config-file/
CIS controls
Version 6.5.1 Minimize And Sparingly Use Administrative Privileges - Minimize administrative privileges and only use administrative accounts when they are required. Implement focused auditing on the use of administrative privileged functions and monitor for anomalous behavior.
Version 7.5.2 Maintain Secure Images - Maintain secure images or templates for all systems in the enterprise based on the organization’s approved configuration standards. Any new system deployment or existing system that becomes compromised should be imaged using one of those images or templates.
