Kubernetes API Server must disable basic authentication to protect information in transit.

STIG ID: CNTR-K8-002620  |  SRG: SRG-APP-000439-CTR-001080 |  Severity: high |  CCI: CCI-002448 |  Vulnerability Id: V-245542

Vulnerability Discussion

Kubernetes basic authentication sends and receives request containing username, uid, groups, and other fields over a clear text HTTP communication. Basic authentication does not provide any security mechanisms using encryption standards. PKI certificate-based authentication must be set over a secure channel to ensure confidentiality and integrity. Basic authentication must not be set in the manifest file.

Check

Change to the /etc/kubernetes/manifests/ directory on the Kubernetes Control Plane. Run the command:
grep -i basic-auth-file *

If "basic-auth-file" is set in the Kubernetes API server 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. Remove the setting "--basic-auth-file".