Configure ImagePolicyWebhook Admission Control

The API server must enforce image admission checks using ImagePolicyWebhook.

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The task

Task

The API server must enforce image admission checks using ImagePolicyWebhook.

Requirements

Enable the ImagePolicyWebhook admission plugin on the API server
Use the provided AdmissionConfiguration file at /etc/kubernetes/admission-config.yaml
Configure ImagePolicyWebhook so that images are denied when the backend is unavailable (defaultAllow: false)

Restart the API server and verify that the admission configuration is active.

Exam

CKS

Domain

Supply Chain Security

Grading

Programmatic · partial credit

Reference

Kubernetes docs ↗

What this tests

Scan images for vulnerabilities, harden Dockerfiles, generate SBOMs, and enforce image policy. On the CKS exam, Supply Chain Security tasks are graded purely on what you build in the cluster — not multiple choice — so the only way to get faster is to do them on a real cluster against a clock.

Practice it for real

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