GSEC Container Security Practice Question
A security engineer wants to ensure that container images are not modified after they are built and pushed to a registry. Which mechanism provides the strongest assurance of image integrity and authenticity?
⚠ Common exam trap
Candidates often confuse vulnerability scanning tools with integrity mechanisms, incorrectly assuming that finding bugs prevents unauthorized modification or guarantees the authenticity of the container image pushed to the registry.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Applying cryptographic digital signatures to container images.
Content trust and image signing using tools like Notary or Cosign ensure that the image pulled by a runtime is exactly the same one pushed by the CI/CD pipeline. By cryptographically signing the manifest, organizations prevent man-in-the-middle attacks and unauthorized registry modifications. This is vital in modern DevSecOps, as compromised images could introduce persistent backdoors or vulnerabilities into the production environment without triggering standard application-level alerts.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Implementing a read-only filesystem for the container at runtime.
Why it's wrong here
While read-only filesystems limit the impact of an exploit by preventing runtime modification of local files, they do not verify the authenticity of the container image itself. This control is a defense-in-depth measure rather than a supply chain integrity validation mechanism for image distribution.
- ✗
Using SHA-256 image digests instead of mutable image tags.
Why it's wrong here
Digests provide content addressability which prevents tag-swapping attacks. However, they do not inherently provide cryptographic proof of the author's identity or verify that the image has not been maliciously tampered with during the transit between the build system and the private registry storage.
- ✓
Applying cryptographic digital signatures to container images.
Why this is correct
Digital signatures provide a verifiable link between the image and the build process. By using a private key to sign the image manifest, the organization ensures that any subsequent modifications to the image data will cause the signature validation check to fail upon deployment.
- ✗
Scanning images for known vulnerabilities using a static analyzer.
Why it's wrong here
Vulnerability scanning identifies known CVEs within the image layers but does not guarantee the integrity or origin of the code. An attacker could potentially modify an image to include a malicious backdoor while still maintaining a clean vulnerability report from the static scanning tools.
About these practice questions
Courseiva writes every GSEC question from scratch — 351 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official GIAC exam blueprint
This GSEC practice question is part of Courseiva's free GIAC certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the GSEC exam.