1.3.5 Ensure that the --root-ca-file argument is set as appropriate

Information

Allow pods to verify the API server's serving certificate before establishing connections.

Rationale:

Processes running within pods that need to contact the API server must verify the API server's serving certificate. Failing to do so could be a subject to man-in-the-middle attacks. Providing the root certificate for the API server's serving certificate to the controller manager with the `--root-ca-file` argument allows the controller manager to inject the trusted bundle into pods so that they can verify TLS connections to the API server.

Solution

Edit the `/etc/kubernetes/controller-manager` file on the master node and set the `KUBE_CONTROLLER_MANAGER_ARGS` parameter to include `--root-ca-file=`: `KUBE_CONTROLLER_MANAGER_ARGS='--root-ca-file='`

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

Impact:

You need to setup and maintain root certificate authority file.

See Also

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

Item Details

Category: IDENTIFICATION AND AUTHENTICATION

References: 800-53|IA-5(2), CSCv6|14.2

Plugin: Unix

Control ID: 23851bbdc3ce975b2a6b787e0e66a2a6f9cfaaf8c023413ae010f3d49bc2caf0