CNTR-K8-001450 - Kubernetes etcd must enable client authentication to secure service.
Kubernetes container and pod configuration are maintained by Kubelet. Kubelet agents register nodes with the API Server, mount volume storage, and perform health checks for containers and pods. Anyone who gains access to Kubelet agents can effectively control applications within the pods and containers. Using authenticity protection, the communication can be protected against man-in-the-middle attacks/session hijacking and the insertion of false information into sessions. The communication session is protected by utilizing transport encryption protocols, such as TLS. TLS provides the Kubernetes API Server with a means to be able to authenticate sessions and encrypt traffic. To enable encrypted communication for Kubelet, the parameter client-cert-auth must be set. This parameter gives the location of the SSL Certificate Authority file used to secure Kubelet communication.
Edit the Kubernetes etcd manifest file in the /etc/kubernetes/manifests directory on the Kubernetes Master Node. Set the value of '--client-cert-auth' to 'true' for the etcd.