The Kubernetes API server must have the secure port set.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-242389	SRG-APP-000033-CTR-000100	CNTR-K8-000350	SV-242389r960792_rule	2025-02-20	2

Description
By default, the API server will listen on what is rightfully called the secure port, port 6443. Any requests to this port will perform authentication and authorization checks. If this port is disabled, anyone who gains access to the host on which the Control Plane is running has full control of the entire cluster over encrypted traffic. Open the secure port by setting the API server's "--secure-port" flag to a value other than "0".

Description

By default, the API server will listen on what is rightfully called the secure port, port 6443. Any requests to this port will perform authentication and authorization checks. If this port is disabled, anyone who gains access to the host on which the Control Plane is running has full control of the entire cluster over encrypted traffic. Open the secure port by setting the API server's "--secure-port" flag to a value other than "0".

ℹ️ Check
Change to the /etc/kubernetes/manifests directory on the Kubernetes Control Plane. Run the command: grep -i secure-port * If the setting "--secure-port" is set to "0" or is not configured in the Kubernetes API manifest file, this is a finding.

✔️ Fix
Edit the Kubernetes API Server manifest file in the /etc/kubernetes/manifests directory on the Kubernetes Control Plane. Set the value of "--secure-port" to a value greater than "0".