Details

Explicitly set a service account private key file for service accounts on the controller manager.

Rationale:

To ensure that keys for service account tokens can be rotated as needed, a separate public/private key pair should be used for signing service account tokens. The private key should be specified to the controller manager with `–service-account-private-key-file` as appropriate.

Solution

Edit the `/etc/kubernetes/controller-manager` file on the master node and set the `KUBE_CONTROLLER_MANAGER_ARGS` parameter to `–service-account-private-key-file=`: `KUBE_CONTROLLER_MANAGER_ARGS=’–service-account-private-key-file=’`

Based on your system, restart the `kube-controller-manager` service. For example: `systemctl restart kube-controller-manager.service`

Impact:

You would need to securely maintain the key file and rotate the keys based on your organization’s key rotation policy.

Supportive Information

The following resource is also helpful.

• https://workbench.cisecurity.org/files/1738

This security hardening control applies to the following category of controls within NIST 800-53: Identification and Authentication.This control applies to the following type of system Unix.

References

• 800-53|IA-5(2)
• CSCv6|14

Source

• Tenable.com/audits