CNTR-K8-000380 - The Kubernetes kubelet must enable explicit authorization.

Information

Kubelet is the primary agent on each node. The API server communicates with each kubelet to perform tasks such as starting/stopping pods. By default, kubelets allow all authenticated requests, even anonymous ones, without requiring any authorization checks from the API server. This default behavior bypasses any authorization controls put in place to limit what users may perform within the Kubernetes cluster. To change this behavior, the default setting of AlwaysAllow for the authorization mode must be set to 'Webhook'.

Solution

Edit the Kubernetes Kubelet file in the/etc/sysconfig/ directory on the Kubernetes Master and Worker nodes.

Set the argument --authorization-mode to 'Webhook'.

Restart each kubelet service after the change is made using the command:
service kubelet restart

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Kubernetes_V1R5_STIG.zip

Item Details

Category: ACCESS CONTROL

References: 800-53|AC-3, CAT|I, CCI|CCI-000213, Rule-ID|SV-242392r712532_rule, STIG-ID|CNTR-K8-000380, Vuln-ID|V-242392

Plugin: Unix

Control ID: df2b12fa9be711f4f9a829847f646b7b5e109d071dd8c575f131368366f11f72