Title

The Kubernetes API server must have Alpha APIs disabled. (Cat II impact)

Discussion

Kubernetes allows alpha API calls within the API server. The alpha features are disabled by default since they are not ready for production and likely to change without notice. These features may also contain security issues that are rectified as the feature matures. To keep the Kubernetes cluster secure and stable, these alpha features must not be used.

Check Content

On the Control Plane, change to the manifests' directory at /etc/kubernetes/manifests and run the command: grep -i feature-gates * Review the "--feature-gates" setting, if one is returned. If the "--feature-gate"s setting is available and contains the "AllAlpha" flag set to "true", this is a finding.

Fix Text

Edit any manifest file that contains the "--feature-gates" setting with "AllAlpha" set to "true". Set the value of "AllAlpha" to "false" or remove the setting completely. (AllAlpha - default=false)

Additional Identifiers

Rule ID: SV-242400r960792_rule

Vulnerability ID: V-242400

Group Title: SRG-APP-000033-CTR-000090

Expert Comments

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