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Secure container image registries by enforcing vulnerability scanning, image signing, SBOM.

Secure container image registries by enforcing vulnerability scanning, image signing, SBOM traceability, and promotion gates that prevent unsafe artifacts from deployment.

Category

Security

Execution

7 steps, sequential + gated

Goal

Secure container image registries by enforcing vulnerability scanning, image signing, SBOM traceability, and promotion gates that prevent unsafe artifacts from deployment.

Scope

Applies to

  • +Secure container registry images
  • +Require scan and signature before image promotion
  • +Implement SBOM and registry hardening controls

Does not cover

  • −Trivial changes outside the workflow domain

Triggers

"Secure container registry images""Require scan and signature before image promotion""Implement SBOM and registry hardening controls""Audit registry for unscanned/unsigned images"

Inputs

  • →Context: environment/system affected
  • →Scope: change boundary
  • →Constraints: policy or hard rules

Invariants

  • 01Images must not be promoted to protected environments without passing scan policy.
  • 02Image authenticity must be verifiable (signature and provenance expectations).
  • 03Mutable tag risk must be controlled (immutability or digest-based promotion).
  • 04SBOM and scan artifacts must be retained and linked to image digests.
  • 05Exceptions must be explicit, reviewed, and time-bounded.

Procedure

  1. Step 1Step 1 — **Baseline registry security posture**
  2. Step 2Step 2 — **Enforce vulnerability scanning**
  3. Step 3Step 3 — **Generate and persist SBOM**
  4. Step 4Step 4 — **Implement signing and verification**
  5. Step 5Step 5 — **Harden registry controls**
  6. Step 6Step 6 — **Integrate CI/CD promotion gate**
  7. Step 7Step 7 — **Continuous reassessment**

Outputs

  • ▸Registry security posture report with prioritized gaps.
  • ▸Scan artifacts and vulnerability summary per image digest.
  • ▸Signed image verification evidence and attestation metadata.
  • ▸SBOM inventory linked to promoted artifacts.
  • ▸Promotion gate report with pass/fail and exception details.

Review Gate

  • [ ]All promoted images pass vulnerability policy thresholds.
  • [ ]Signature verification is enforced in promotion path.
  • [ ]SBOM is generated and traceable to image digests.
  • [ ]Tag immutability/digest controls prevent silent artifact replacement.
  • [ ]Exceptions are documented with rationale, owner, and expiry.