cyberstrikeus CIS Kubernetes Benchmark v1.12.0 - Control 4.1.9
Description
Ensure that if the kubelet refers to a configuration file with the --config argument, that file has permissions of 600 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.
Impact
None
Audit Procedure
Step 1: Set the kubelet config yaml variable
Automated AAC auditing has been modified to allow CIS-CAT to input a variable for the <PATH>/<FILENAME> of the kubelet config yaml file.
Please set $kubelet_config_yaml=<PATH> based on the file location on your system.
For example:
export kubelet_config_yaml=/var/lib/kubelet/config.yaml
Step 2: Verify file permissions
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 /var/lib/kubelet/config.yaml
Verify that the permissions are 600 or more restrictive.
Remediation
Run the following command (using the config file location identified in the Audit step):
chmod 600 /var/lib/kubelet/config.yaml
Default Value
By default, the /var/lib/kubelet/config.yaml file as set up by kubeadm has permissions of 600.
References
CIS Controls
| Controls Version | Control | IG 1 | IG 2 | IG 3 |
|---|---|---|---|---|
| v8 | 3.3 Configure Data Access Control ListsConfigure data access control lists based on a user's need to know. Apply data access control lists, also known as access permissions, to local and remote file systems, databases, and applications. | ● | ● | ● |
| v7 | 14.6 Protect Information through Access Control ListsProtect all information stored on systems with file system, network share, claims, application, or database specific access control lists. | ● | ● | ● |
Profile Applicability
- Level 1 - Worker Node
Assessment Status
Automated