Enforce Container Immutability

A Deployment is running with an insecure container security context.

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The task

Task

A Deployment is running with an insecure container security context.

Requirements

Update the container security context of Deployment mutable-app to enforce immutability:

runAsUser: 30000
readOnlyRootFilesystem: true
allowPrivilegeEscalation: false

Verify that the Deployment is available.

Exam

CKS

Domain

Minimize Microservice Vulnerabilities

Grading

Programmatic · partial credit

Reference

Kubernetes docs ↗

What this tests

Apply Pod Security Standards, securityContext, and mTLS, and protect secrets at rest. On the CKS exam, Minimize Microservice Vulnerabilities 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

prepium.sh drops you into your own isolated Kubernetes cluster in the browser — no install, no credit card. You solve the task in a real terminal, hit validate, and a programmatic checker scores exactly what you got right and wrong (with partial credit). The canonical solution unlocks after you attempt it, so you learn the fast, exam-ready way to do it.

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