SOTA DevSecOps & Supply Chain Security

Purpose

This skill encodes the 2026 state of the art for securing the path from source code to running workload: pipeline hardening, dependency and artifact supply chain, build integrity, analysis gates, IaC/deployment security, and runtime policy enforcement. It is defensive: every rule exists to prevent a real, named class of compromise (token theft, workflow injection, dependency confusion, tag mutation, state leakage, bypassable gates).

Two operating modes. Pick one explicitly at the start of the task.

BUILD mode

Use when creating or extending pipelines, Dockerfiles, Terraform, GitOps configs, or dependency tooling.

1. Identify which stages of the source-to-production path the task touches (source → CI → build → artifact → deploy → runtime) and read the matching rules files from the index below BEFORE writing config.
2. Default to the most restrictive option that works: read-only tokens, OIDC over stored keys, SHA pins, digest pins, frozen lockfile installs, non-root distroless runtime. Loosen only with a written reason in a comment.
3. Every gate you add must be a required check that fails closed. A scanner whose job is continue-on-error: true is documentation, not a control.
4. Ship the verification path with the signing path: if you generate provenance/signatures/ SBOMs, also wire the consumer (admission policy, gh attestation verify, cosign verify in CD). Unverified attestations are dead weight.
5. State assumptions you could not verify (org settings, branch protection, registry config) at the end of your work so the operator can confirm them.

AUDIT mode

Use when reviewing existing pipelines, workflows, Dockerfiles, IaC, or dependency posture.

Process: enumerate workflows/build files/IaC; for each, walk the relevant Audit checklist at the end of every rules file; report findings in the format below; do not report style nits as security findings.

Severity conventions

Severity	Meaning	Examples
Critical	Remote compromise of pipeline, secrets, or artifacts is achievable now by an external party	pull_request_target checking out PR head with secrets; script injection from PR title into run:; long-lived cloud admin keys in repo secrets used by fork-triggered workflow; unauthenticated registry push
High	Compromise achievable by a contributor, or a single upstream event away	Actions pinned to mutable tags; no branch protection on default branch; CI token with write-all; no lockfile / unfrozen installs; Terraform applies from un-reviewed plans with admin creds
Medium	Weakens defense in depth or detection	Missing SBOM/provenance; scanners non-blocking; no drift detection; mutable image tags in deploy manifests; no secret-scanning push protection
Low	Hygiene, hardening headroom	Missing .dockerignore; unpinned dev-only tooling; verbose CI logs; missing CODEOWNERS on workflows

Severity is judged by reachability: who can trigger the path (anonymous > fork PR author > org member > admin) and what it yields (secrets/artifact write > code exec in CI > info leak).

Finding format

[SEVERITY] <short title>
File: <path>:<line>
Issue: <what is wrong, one or two sentences>
Attack path: <who exploits it and how — concrete, not theoretical>
Fix: <exact config change, with snippet when short>
Rule: <rules file # and section>

End every audit with: counts per severity, the top 3 fixes by risk reduction per effort, and an explicit list of what was OUT of scope (org settings, registry config, runner infra you could not see).

Rules index

File	Read this when...
rules/01-pipeline-security.md	Writing or auditing CI workflows: GITHUB_TOKEN permissions, OIDC to cloud, SHA-pinning actions, pull_request_target / fork PR handling, script injection, self-hosted runners, branch/environment protection, signed commits, workflow-file ownership, proving the pipeline has ever executed (run it locally against a fresh clone; skipped and platform-refused runs both look like "CI exists"); AI coding agents as CI actors (§1.5a) — and why §1.5's env: fix is a shell defence that does not apply to a sink which interprets the value
rules/02-provenance-signing.md	Artifact integrity: SLSA levels, build provenance, in-toto attestations, Sigstore/cosign keyless signing, GitHub artifact attestations, npm/PyPI trusted publishing, release and tag integrity, verification at deploy time
rules/03-dependencies.md	Anything touching package manifests or lockfiles: frozen installs, dependency review gates, dependency confusion and registry scoping, typosquatting and malicious-package indicators, SBOM (CycloneDX/SPDX), vuln scanning with osv-scanner/grype, VEX and triage discipline, Renovate/Dependabot strategy (including a pin no bot can parse, which is a freeze rather than a pin), vendoring
rules/10-inert-dependencies.md	The declared-but-not-reached sweep: a dependency, module or plugin that is installed, pinned, scanned and never runs. Reachability from a real entrypoint rather than import presence; the per-ecosystem tools and the blind spot each one has; deletion-as-proof (no tool's silence is evidence); the leverage ratio; upstream health fetched from a live primary source and reported as dates, not adjectives; the four-bucket classification and the do-not-reimplement list; and why "unused" is an absence claim that needs two independent methods
rules/04-build-containers.md	Dockerfiles and build systems: hermetic/reproducible builds, multi-stage builds, build secrets, base image strategy (distroless/Chainguard, digest pinning), image scanning, registry security, immutable tags
rules/05-analysis-gates.md	The scanners themselves: SAST (Opengrep/CodeQL), secret scanning and push protection, IaC scanning (checkov/trivy/tfsec), DAST, license compliance, and flaky-test discipline; the PR gate stack
rules/09-gates-that-hold.md	A warning on a PASSING run may have no path to a human — pre-commit discards a passing hook's output entirely (§4) · Whether any of it actually gates — a property of the pipeline, not the scanner. What SSDF/CRA/Scorecard/SLSA do and don't require (all want a record the scan ran, none want evidence it could have failed, so a negative control is a house rule); required checks and bypass patterns; a gate whose scope shrank under an innocent refactor; a gate only gates if failing it makes the artifact unconsumable — build to a candidate identifier the deploy watcher provably cannot match, promote by same-digest retag after the last gate; a verdict that dies with the executor (/dev/termination-log, budgeted from the container count) so the operator gets a cause instead of exit code 1; and reproducing the gate's exact invocation rather than a convenient equivalent
rules/06-iac-deployment.md	Terraform and delivery: state security, plan/apply separation with review, saved-plan apply, drift detection, GitOps (Flux/Argo) security model, progressive delivery (canary/blue-green/flags), rollback readiness, build-once-promote-many environment parity
rules/07-runtime-ops.md	Runtime enforcement and operations: admission control for signed images (Kyverno/policy-controller), policy as code (OPA/Kyverno) with tests, Pod Security, incident-ready CI/CD audit logging, deployment traceability, backup/restore testing, break-glass
rules/08-registry-security.md	Securing the container/artifact registry as infrastructure: the registry as a tier-0 supply-chain trust anchor; no anonymous push/pull and least-privilege robot/CI accounts (Zot accessControl, Harbor robots, cloud IAM); immutable tags and digest pinning to defeat tag mutation; OCI referrers for signature/SBOM/scan storage; scan-on-push and continuous re-scan; pull-through cache and image-layer dependency confusion; retention/GC that won't break running deploys; registry HA/backup; network hardening (no anonymous internet exposure, no hostNetwork, TLS)

When a task spans stages (most do), read every matching file. For a full pipeline audit, read all ten.

Top 10 non-negotiables

Violations of these are at minimum High in AUDIT mode and must never be introduced in BUILD mode:

1. Top-level permissions: block in every workflow, starting from contents: read (or {}), elevating per job only. Never rely on org/repo default token permissions.
2. No long-lived cloud credentials in CI secrets. Use OIDC federation with sub-claim conditions scoped to repo + ref/environment.
3. Pin third-party actions (and base images) by full commit SHA / digest, with a version comment, updated by Renovate/Dependabot. Tags are mutable attack surface.
4. Never combine untrusted PR code with secrets or write tokens. pull_request_target (or workflow_run) must not check out or execute PR head content; treat fork artifacts as hostile input.
5. No untrusted expression interpolation in run: scripts. PR titles, branch names, issue bodies, commit messages go through env: indirection, quoted.
6. Lockfiles committed; CI installs are frozen (npm ci, --frozen-lockfile, --require-hashes, --locked). A build that resolves versions at build time is not reproducible and not reviewable.
7. Security gates are required status checks that fail closed. No continue-on-error, no || true, no unprotected default branch, no "admins bypass".
8. Build once, promote the same digest through environments. Deploy manifests reference image digests (or signed, verified tags), never :latest.
9. Terraform state is secret material: remote encrypted backend, least-privilege access, plan on PR with read-only creds, apply only a reviewed saved plan via a protected environment.
10. Production admission requires verified provenance: signed images (cosign/Kyverno verifyImages or equivalent), non-root, pinned digests — enforce, don't just audit.

If the user asks for something that violates a non-negotiable, implement the secure alternative and explain the delta; only comply after they acknowledge the risk explicitly.