supply-chain-attack-response – DevOps & Infrastructure skill for AI agents

> ⚠️ AUTHORIZED USE ONLY

> This skill is for educational purposes or authorized security assessments only.

> You must have explicit, written permission from the system owner before using this tool.

> Misuse of this tool is illegal and strictly prohibited.

> Mandatory confirmation gate

> Before running any command that probes, exploits, changes, persists on, extracts data from, or attempts credential access against a target:

> 1. Ask the user to state the exact target URL, IP, account, or resource.

> 2. Ask the user to confirm written authorization and the permitted scope.

> 3. Show the exact command(s) and explain their expected effect.

> 4. Wait for explicit confirmation in the current conversation.

>

> Without that confirmation, remain read-only and provide defensive guidance only. Prefer a sandbox, disposable VM, or controlled lab.

Supply Chain Attack Response

Software supply chain attacks target the dependencies, build systems, and distribution channels that developers trust implicitly. When a package on PyPI, npm, or crates.io is compromised, downstream consumers may receive malicious content; execution and exposure depend on installation/build/runtime paths. This skill provides detection techniques, emergency response playbooks, and hardening strategies to protect your software supply chain end to end.

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2. Detection

2.1 npm Audit

# Full audit of installed packages
npm audit

# JSON output for programmatic processing
npm audit --json | jq '.vulnerabilities | to_entries[] | select(.value.severity == "critical")'

# Review a repair proposal in an isolated trusted copy; do not auto-fix an incident host.
npm audit fix --dry-run --ignore-scripts

# Check the current reviewed Socket CLI documentation and data-transfer policy before installing/running it.

2.2 pip Audit

# Install pip-audit (maintained by Google/OSSF)
pip install pip-audit

# Audit known advisories for the current environment (select OSV explicitly when required)
pip-audit

# Audit a requirements file directly
pip-audit --no-deps --disable-pip -r requirements.txt --format json

# pip-audit detects known vulnerability advisories, not typosquatting; --strict affects dependency-audit failures.

2.3 Cargo Audit

# Install cargo-audit
cargo install cargo-audit

# Run audit against RustSec Advisory Database
cargo audit

# JSON output for CI integration
cargo audit --json

# Check for yanked crates
cargo audit --deny yanked

2.4 Sigstore / Cosign Verification

# Verify a container image signature with cosign
cosign verify \
  --certificate-identity "https://github.com/myorg/myrepo/.github/workflows/build.yml@refs/heads/main" \
  --certificate-oidc-issuer "https://token.actions.githubusercontent.com" \
  ghcr.io/myorg/myimage@sha256:<full-reviewed-digest>

# Verify an artifact with sigstore-python
pip install sigstore
python -m sigstore verify identity \
  --cert-identity "[email protected]" \
  --cert-oidc-issuer "https://accounts.google.com" \
  artifact.tar.gz

2.5 SLSA Provenance Checks

# Install slsa-verifier
go install github.com/slsa-framework/slsa-verifier/v2/cli/slsa-verifier@latest

# Verify provenance of a binary
slsa-verifier verify-artifact my-binary \
  --provenance-path my-binary.intoto.jsonl \
  --source-uri github.com/myorg/myrepo \
  --source-tag v1.2.3

---

3. Emergency Response Playbook

When a dependency is confirmed compromised, execute these steps in order.

Step 1: Contain -- Pin and Freeze

# Pin the last known-good version immediately in package.json
npm install <package>@<safe-version> --save-exact --ignore-scripts
# Only in a clean isolated repair copy, after preserving incident evidence.

# For pip, pin with hash verification
python -m pip download --only-binary=:all: --require-hashes -r reviewed-requirements.txt -d ./vendor/
# reviewed-requirements.txt must pin all dependencies and verified artifact hashes.

# For cargo, pin in Cargo.toml
# Replace: some_crate = "^1.2" with:
# some_crate = "=1.2.3"
cargo update -p some_crate --precise 1.2.3

Step 2: Audit Exposure

# Determine which versions you pulled and when
# npm
npm ls <compromised-package>
cat package-lock.json | jq '.packages | to_entries[] | select(.key | contains("<compromised-package>"))'

# pip
pip show <compromised-package>
pip cache list <compromised-package>

# Check git history for when the dependency version changed
git log --all -p -- package-lock.json | grep -A2 -B2 "<compromised-package>"

Step 3: Scan for Indicators of Compromise

# Search for known IOCs from the advisory
grep -r "suspicious-domain.com" ./node_modules/<compromised-package>/
rg --fixed-strings -- "atob" ./node_modules/<compromised-package>/

# Check for unexpected post-install scripts
cat node_modules/<compromised-package>/package.json | jq '.scripts'

# For Python packages, inspect setup.py and __init__.py
rg -l --glob "*.py" -- "subprocess|os[.]system|exec|eval" ./reviewed-package-copy/

Step 4: Notify Stakeholders

SUBJECT: [SECURITY INCIDENT] Compromised dependency: <package-name>

SEVERITY: Critical
IMPACT: <package-name> versions <affected-range> contain malicious code.
AFFECTED SYSTEMS: <list of repos/services consuming this dependency>
STATUS: Contained -- pinned to safe version <safe-version>

ACTIONS TAKEN:
1. Pinned all repositories to last known-good version
2. Initiated audit of all systems that pulled affected versions
3. Scanning for indicators of compromise

RECOMMENDED ACTIONS:
- Do NOT deploy any build that consumed affected versions
- Review CI/CD logs for the timeframe <start> to <end>
- Rotate any secrets that were accessible to the build environment

Step 5: Replace or Fork

# If the package maintainer account was compromised, fork the last safe version
git clone https://github.com/original-author/<package>.git
cd <package>
git checkout v<safe-version>
# Publish to your private registry or vendor directly

# For npm, point to your fork via package.json
# "dependencies": { "<package>": "git+https://github.com/yourorg/<package>.git#v1.2.3" }

---

4. Lockfile Auditing

Lockfiles are your first line of defense. Tampered or inconsistent lockfiles indicate something is wrong.

4.1 Verify Lockfile Integrity

# npm: ensure lockfile matches package.json (fails CI if out of sync)
npm ci --ignore-scripts

# Yarn: check lockfile integrity
YARN_ENABLE_SCRIPTS=false yarn install --immutable  # modern Yarn; verify installed version

# pip: generate a hash-locked requirements file
pip-compile --generate-hashes requirements.in -o requirements.txt

# Verify no unexpected changes in lockfile during PR
git diff --name-only origin/main...HEAD | grep -E "(package-lock|yarn.lock|Cargo.lock|requirements.txt)"

4.2 Detect Typosquatting

# Use separately reviewed package-risk tooling; do not fetch an unverified npx tool during containment.

# Python: check package names against popular packages
# pip-audit is not a typosquatting detector.

# Custom check: compare package names to known popular packages
# Illustrative SequenceMatcher similarity against a tiny list; this is not edit distance or a malware verdict.
python3 -c "
import json, sys
from difflib import SequenceMatcher
with open('package-lock.json') as f:
    lock = json.load(f)
popular = ['express','lodash','react','axios','chalk','debug','commander','inquirer']
for pkg in lock.get('packages', {}):
    name = pkg.split('node_modules/')[-1] if 'node_modules/' in pkg else pkg
    for p in popular:
        ratio = SequenceMatcher(None, name, p).ratio()
        if 0.75 < ratio < 1.0 and name != p:
            print(f'WARNING: {name} is suspiciously similar to {p} (similarity: {ratio:.2f})')
"

4.3 Lockfile Diff in CI

# .github/workflows/lockfile-check.yml
name: Lockfile Audit
on: pull_request
jobs:
  audit:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
      - name: Check for lockfile changes
        run: |
          LOCKFILES="package-lock.json yarn.lock pnpm-lock.yaml Cargo.lock requirements.txt poetry.lock"
          for f in $LOCKFILES; do
            if git diff --name-only origin/main...HEAD | grep -q "$f"; then
              echo "::warning::Lockfile $f was modified -- review dependency changes carefully"
              git diff origin/main...HEAD -- "$f" | head -100
            fi
          done
      - name: Run npm audit
        if: hashFiles('package-lock.json') != ''
        run: npm audit --audit-level=high

---

5. Package Pinning and Verification

5.1 pip Hash Checking

# requirements.txt with hashes (generated by pip-compile --generate-hashes)
<package>==<reviewed-version> \
    --hash=sha256:<full-verified-artifact-hash>

# Install with mandatory hash verification
pip install --require-hashes -r requirements.txt

… (full content is in the download package)