The Kubernetes Kubelet must have anonymous authentication disabled. (Cat I impact)
A user who has access to the Kubelet essentially has root access to the nodes contained within the Kubernetes Control Plane. To control access, users must be authenticated and authorized. By allowing anonymous connections, the controls put in place to secure the Kubelet 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 must be disabled and only enabled when necessary.
Change to the /etc/sysconfig/ directory on the Kubernetes Master Node. Run the command: grep -i anonymous-auth kubelet If the setting "anonymous-auth" is set to "true" or the parameter not set in the Kubernetes Kubelet configuration file, this is a finding.
Edit the Kubernetes Kubelet file in the/etc/sysconfig/ directory on the Kubernetes Master Node. Set the argument "--anonymous-auth" to "false". Restart kubelet service using command: service kubelet restart
Rule ID: SV-242391r712529_rule
Vulnerability ID: V-242391
Group Title: SRG-APP-000033-CTR-000090
The information system enforces approved authorizations for logical access to information and system resources in accordance with applicable access control policies.