SLSA Provenance for react-lite-youtube-embed

November 15, 2025 · View on GitHub

What is SLSA?

SLSA (Supply chain Levels for Software Artifacts) is a security framework that helps protect against supply chain attacks. It provides verifiable proof about how your software was built and where it came from.

Why SLSA Matters for This Project

This package is distributed via NPM and installed by thousands of developers. SLSA provides:

  • 🔒 Tamper-proof builds - Cryptographic proof that packages weren't modified after building
  • 🔍 Build transparency - Verifiable evidence of the build environment and process
  • 🛡️ Attack prevention - Protection against compromised build systems and malicious injections
  • ✅ Trust verification - Users can verify packages came from official GitHub Actions

SLSA Level

This project achieves SLSA Build Level 3:

  • ✅ Build process is fully scripted/automated
  • ✅ Provenance is generated automatically
  • ✅ Build service is hardened (GitHub Actions)
  • ✅ Provenance is non-forgeable (signed by GitHub)
  • ✅ Build isolation (separate runners per build)

How It Works

Every release automatically:

  1. Builds the package in GitHub Actions
  2. Generates a cryptographically signed provenance attestation
  3. Publishes the attestation to the NPM registry alongside the package
  4. Links the attestation to the GitHub release

What's in the Provenance?

The provenance attestation includes:

  • Source repository and commit SHA
  • Build workflow and runner details
  • Build inputs (branch, tag, environment variables)
  • Build outputs (package tarball hash)
  • Digital signature from GitHub's Sigstore

Verifying SLSA Provenance

For Package Users

# Install the package
npm install react-lite-youtube-embed

# Verify the provenance
npm audit signatures

This checks that:

  • Package was published from the official GitHub repository
  • Build came from a GitHub Actions workflow
  • Package tarball matches the attested hash

Option 2: Using slsa-verifier

# Install slsa-verifier
npm install -g @sigstore/cli

# Download the package
npm pack react-lite-youtube-embed

# Verify the package (replace with actual version)
npx @sigstore/cli verify ibrahimcesar-react-lite-youtube-embed-3.0.5.tgz \
  --certificate-identity-regexp="^https://github.com/ibrahimcesar/react-lite-youtube-embed" \
  --certificate-oidc-issuer=https://token.actions.githubusercontent.com

Option 3: View Provenance on NPM

Visit the package page on npm: https://www.npmjs.com/package/@ibrahimcesar/react-lite-youtube-embed

Look for the "Provenance" badge showing:

  • Source repository
  • Build workflow
  • Commit SHA

For Maintainers

Viewing Generated Attestations

After each release, you can find the provenance:

  1. On GitHub Releases

  2. In GitHub Actions Artifacts

    • Navigate to the workflow run
    • Download provenance-attestations artifact
    • Contains .jsonl file with full attestation

  3. On NPM Registry

    • Visit package page
    • Click on "Provenance" badge
    • Shows verified build information

Implementation Details

Workflows with SLSA

This project generates SLSA provenance in:

  1. Automated Release Workflow (.github/workflows/auto-release.yml)

    • Manual dispatch workflow
    • Generates provenance before NPM publish
    • Publishes attestation automatically

  2. Manual Release Workflow (.github/workflows/release.yml)

    • Triggered on GitHub release creation
    • Generates provenance before NPM publish
    • Publishes attestation automatically

Technical Implementation

We use the official SLSA generator:

  • Generator: slsa-framework/slsa-github-generator
  • Version: Latest stable release
  • Provenance Level: SLSA Build Level 3
  • Attestation Format: In-toto provenance (v1.0)

Permissions Required

The workflows require specific permissions:

permissions:
  contents: read      # Read repository
  actions: read       # Read workflow info
  id-token: write     # Sign attestations
  packages: write     # Publish to GitHub Packages
  attestations: write # Write provenance

Security Considerations

What SLSA Protects Against

✅ Build tampering - Detects if build outputs were modified ✅ Compromised dependencies - Tracks build inputs ✅ Malicious injections - Verifies build process integrity ✅ Account compromise - Builds are isolated in GitHub Actions ✅ Fake packages - Cryptographic proof of authentic builds

What SLSA Does NOT Protect Against

❌ Vulnerabilities in source code - Use security scanning ❌ Compromised dependencies - Use dependency scanning (npm audit) ❌ Social engineering - Use code review and access controls ❌ Runtime attacks - Use application security best practices

Troubleshooting

Verification Fails

If npm audit signatures fails:

  1. Check npm version - Requires npm 8.x or higher

    npm --version
npm install -g npm@latest

  2. Check registry - Provenance only works with official npm registry

    npm config get registry
# Should be: https://registry.npmjs.org/

  3. Check package version - Ensure using a version with provenance (3.0.6+)

Missing Provenance

If a release is missing provenance:

  1. Check workflow logs - Look for provenance generation step
  2. Check permissions - Ensure id-token: write and attestations: write are set
  3. Retry release - Re-run the workflow

SLSA Badge Not Showing on NPM

NPM may take a few minutes to process and display the provenance badge after publishing.

Resources

Questions?

Status: ✅ SLSA Level 3 enabled for all releases starting from v3.0.6

Last Updated: November 15, 2025