Supply Chain Dependency Security

Supply Chain Dependency Security

Threat Model (2025–2026)

The dominant supply-chain threat is maintainer account takeover of legitimate, widely-trusted packages — not typosquatting. Your CVE scanner will not catch these.

Active campaigns:

• Shai-Hulud: 500+ npm packages compromised via maintainer account takeover
• TeamPCP: Trivy, Checkmarx, LiteLLM, Bitwarden CLI, SAP CAP — targeted at security tooling
• axios: 100M weekly downloads; compromise via release tag hijack
• LiteLLM 1.82.8: malicious .pth file injected for persistent execution on every Python startup

Review Checklist

Lockfiles

• Lockfile committed (package-lock.json, yarn.lock, poetry.lock, uv.lock, pixi.lock, conda-lock.yml)
• Lockfile is used in CI (npm ci, pip install --require-hashes, uv sync --frozen, pixi install)
• No floating version specs in production paths (e.g., *, >=x without upper bound in lockfile-less environments)

Install-time script execution

• npm ci --ignore-scripts (or ignore-scripts=true in .npmrc) in all CI environments
• preinstall/postinstall hooks are the dominant execution vector — verify no hooks run untrusted code
• Python: check for unexpected .pth files that execute on every interpreter start:

  find $(python -c "import site; print(site.getsitepackages()[0])") -name "*.pth"
  

Dependency freshness and cooldown

• New dependencies are held for ≥7 days before merging — most malicious releases are yanked within hours
• Version pins in lockfile match expected package metadata (author, homepage, hash)
• No unpinned latest or * in production dependency specs

Incident response

When a compromise is reported:

1. Identify affected version range from the advisory
2. Check if that version range is in the lockfile
3. Check if the install was cached (CI cache may still contain the compromised version)
4. Rotate any secrets or tokens accessible from the CI environment where the package ran
5. Check for persistence artifacts: .pth files, postinstall side effects, modified node_modules/.bin/

Findings format

Name the vulnerability class, cite the package name + version + advisory or campaign name, state blast radius (what can the package access at install time), and propose the fix (version pin, lockfile update, --ignore-scripts).