| By default, the API server will listen on two ports. One port is the secure port and the other port is called the "localhost port". This port is also called the "insecure port", port 8080. Any requests to this port bypass authentication and authorization checks. If this port is left open, anyone who gains access to the host on which the Control Plane is running can bypass all authorization and authentication mechanisms put in place, and have full control over the entire cluster.
Close the insecure port by setting the API server's --insecure-port flag to "0", ensuring that the --insecure-bind-address is not set.