Performing SCA Dependency Scanning with Snyk

When to Use

• When applications use open-source packages that may contain known vulnerabilities
• When compliance requires tracking and remediating vulnerable dependencies (PCI DSS, SOC 2)
• When needing automated fix PRs for vulnerable dependencies in CI/CD
• When license compliance requires visibility into open-source license obligations
• When continuous monitoring is needed for newly disclosed vulnerabilities in deployed dependencies

Do not use for scanning proprietary application code for logic vulnerabilities (use SAST), for runtime vulnerability detection (use DAST), or for container OS package scanning alone (use Trivy for a free alternative).

Prerequisites

• Snyk account (free tier covers up to 200 tests per month for open source)
• Snyk CLI installed or Snyk GitHub/GitLab integration configured
• SNYK_TOKEN environment variable set with API authentication token
• Project with supported package manifests: package.json, requirements.txt, pom.xml, go.mod, Gemfile, etc.

Workflow

Step 1: Install and Authenticate Snyk CLI

# Install Snyk CLI
npm install -g snyk

# Authenticate with Snyk
snyk auth $SNYK_TOKEN

# Test the connection
snyk test --json | jq '.summary'

Step 2: Scan Dependencies in CI/CD Pipeline

# .github/workflows/dependency-scan.yml
name: Dependency Security Scan

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]
  schedule:
    - cron: '0 8 * * 1'  # Weekly Monday 8am

jobs:
  snyk-scan:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: '20'

      - name: Install dependencies
        run: npm ci

      - name: Run Snyk to check for vulnerabilities
        uses: snyk/actions/node@master
        env:
          SNYK_TOKEN: ${{ secrets.SNYK_TOKEN }}
        with:
          args: >
            --severity-threshold=high
            --fail-on=upgradable
            --json-file-output=snyk-results.json

      - name: Upload results to Snyk
        if: always()
        uses: snyk/actions/node@master
        env:
          SNYK_TOKEN: ${{ secrets.SNYK_TOKEN }}
        with:
          command: monitor
          args: --project-name=${{ github.repository }}

      - name: Upload SARIF
        if: always()
        run: |
          npx snyk-to-html -i snyk-results.json -o snyk-report.html

Step 3: Configure Snyk for Multiple Languages

# Python project scanning
snyk test --file=requirements.txt --severity-threshold=high --json > snyk-python.json

# Java/Maven project
snyk test --file=pom.xml --severity-threshold=medium --json > snyk-java.json

# Go module scanning
snyk test --file=go.mod --severity-threshold=high --json > snyk-go.json

# Docker image dependency scanning
snyk container test myapp:latest --severity-threshold=high --json > snyk-container.json

# Monorepo: scan all projects
snyk test --all-projects --severity-threshold=high --json > snyk-all.json

# IaC scanning (bonus)
snyk iac test terraform/ --severity-threshold=medium --json > snyk-iac.json

Step 4: Configure Snyk Policies for Organization

# .snyk policy file
version: v1.25.0
ignore:
  SNYK-JS-LODASH-1018905:
    - '*':
        reason: "Prototype pollution in lodash. Not exploitable in our usage - no user input reaches affected function."
        expires: 2026-06-01T00:00:00.000Z
        created: 2026-02-23T00:00:00.000Z

  SNYK-PYTHON-REQUESTS-6241864:
    - '*':
        reason: "SSRF in requests redirect handling. Mitigated by allowlist at proxy layer."
        expires: 2026-04-01T00:00:00.000Z

patch: {}

# Severity threshold for CI failures
failOnSeverity: high

Step 5: Enable Automated Fix Pull Requests

# Snyk fix: generate fix PRs for vulnerable dependencies
snyk fix --dry-run  # Preview changes

# Apply fixes locally
snyk fix

# Enable auto-fix PRs via Snyk dashboard:
# 1. Navigate to Organization Settings > Integrations > GitHub
# 2. Enable "Automatic fix pull requests"
# 3. Set "Fix only direct dependencies" or "Fix direct and transitive"
# 4. Configure branch target (main or develop)

Step 6: License Compliance Scanning

# Check license compliance
snyk test --json | jq '.licensesPolicy'

# Snyk license policy configuration via organization settings:
# - Approved licenses: MIT, Apache-2.0, BSD-2-Clause, BSD-3-Clause, ISC

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