CNTR-K8-000360 - The Kubernetes API server must have anonymous authentication disabled.

Information

The Kubernetes API Server controls Kubernetes via an API interface. A user who has access to the API essentially has root access to the entire Kubernetes cluster. To control access, users must be authenticated and authorized. By allowing anonymous connections, the controls put in place to secure the API can be bypassed.

Setting anonymous authentication to 'false' also disables unauthenticated requests from kubelets.

While there are instances where anonymous connections may be needed (e.g., health checks) and Role-Based Access Controls (RBAC) are in place to limit the anonymous access, this access should be disabled, and only enabled when necessary.

Solution

Edit the Kubernetes API Server manifest file in the /etc/kubernetes/manifests directory on the Kubernetes Master Node. Set the argument --anonymous-auth to 'false'.

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-242390r712526_rule, STIG-ID|CNTR-K8-000360, Vuln-ID|V-242390

Plugin: Unix

Control ID: 9c9060ce76e181e4d4c80f7013b6b3bd535f273617388de92f2ab2e15215e1e5