In a Kubernetes cluster, Control Plane controls Nodes, Nodes control Pods, Pods control containers, and containers control applications. But what controls the Control Plane?

Kubernetes exposes APIs that let you configure the entire Kubernetes cluster management lifecycle. Thus, securing access to the Kubernetes API is one of the most security-sensitive aspects to consider when considering Kubernetes security. Even the recently published Kubernetes hardening guide by NSA also suggests to “Use strong authentication and authorization to limit user and administrator access as well as to limit the attack surface” as one of the essential security measures to consider while securing the Kubernetes cluster.