Security Review Skill

Ensures all code follows security best practices and identifies potential vulnerabilities.

When to Activate

• Implementing authentication or authorization
• Handling user input or file uploads
• Creating new API endpoints
• Working with secrets or credentials
• Implementing payment features
• Storing or transmitting sensitive data
• Integrating third-party APIs

Security Checklist Categories

Review each category. See references/vulnerability-patterns.md for WRONG/CORRECT code examples.

1. Secrets Management -- No hardcoded secrets; all in env vars; .env* gitignored
2. Input Validation -- Schema validation; file upload size/type/extension checks
3. SQL Injection -- Parameterized queries only; no string concatenation
4. Auth & Authorization -- httpOnly cookies; RBAC; row-level/object-level authorization where needed
5. XSS Prevention -- DOMPurify for user HTML; CSP headers configured
6. CSRF Protection -- CSRF tokens on state-changing ops; SameSite=Strict cookies
7. Rate Limiting -- All endpoints rate-limited; stricter on expensive operations
8. Data Exposure -- No secrets in logs; generic error messages to users
9. High-Risk Integrations -- Payments, wallets, third-party APIs, and webhooks validated when present
10. Dependencies -- npm audit clean; lock files committed; Dependabot enabled

Full checkbox checklist: assets/security-checklist.md

Pre-Deployment Checklist

Before ANY production deployment, confirm ALL of the following:

• No hardcoded secrets, all in env vars
• All user inputs validated
• All queries parameterized
• User content sanitized (XSS)
• CSRF protection enabled
• Proper token handling (httpOnly cookies)
• Authorization role checks in place
• Rate limiting on all endpoints
• HTTPS enforced
• Security headers configured (CSP, X-Frame-Options)
• No sensitive data in error messages or logs
• Dependencies up to date, no vulnerabilities
• CORS properly configured
• File uploads validated (size, type)

References

• references/vulnerability-patterns.md -- All WRONG/CORRECT code examples by vulnerability type
• assets/security-checklist.md -- Full security review checklist (markdown checkboxes)
• OWASP Top 10
• Next.js Security
• Web Security Academy

---

Security is not optional. One vulnerability can compromise the entire platform. When in doubt, err on the side of caution.