conceptDevSecOps~1 min readUpdated Apr 23, 2026

Container Security

Definition

Container security is the practice of reducing risk in how containerized applications are built, configured, shipped, and run.

Why it matters

Containers make delivery easier, but they also package software, dependencies, configuration, and privilege assumptions into a highly portable unit. Weak base images, broad privileges, and poor defaults can scale insecure patterns quickly. Container security is broader than image-scanning: scanning is one useful control, but the full topic includes base image trust, privilege design, build context, runtime posture, and promotion discipline.

Attacker perspective

Attackers look for: - overly privileged containers - weak or bloated base images - secrets baked into images - exposed admin/debug tooling - drift between what the image contains and what teams think it contains

Defender perspective

Defenders should: - reduce image complexity - control privileges and capabilities carefully - keep build context and image contents intentional - separate build hygiene from runtime assumptions - review how images are sourced and promoted

Practical examples

  • a container runs as root unnecessarily
  • debug tools and credentials are baked into production images
  • teams inherit a base image without understanding its maintenance state

References

  • Foundational: NIST SP 800-218 SSDF — https://csrc.nist.gov/pubs/sp/800/218/final
  • Foundational: CISA Secure by Design — https://www.cisa.gov/resources-tools/resources/secure-by-design