# Aperion Gatekeeper Reference Documentation

This folder contains research, best practices, and improvement plans for the Gatekeeper security component.

## Contents

| Document | Purpose |
|----------|---------|
| [GAP_ANALYSIS.md](GAP_ANALYSIS.md) | **START HERE** - Complete gap analysis and improvement roadmap |
| [HMAC_BEST_PRACTICES.md](HMAC_BEST_PRACTICES.md) | HMAC security guidelines and implementation patterns |
| [OWASP_SESSION_MANAGEMENT.md](OWASP_SESSION_MANAGEMENT.md) | Session/token handling per OWASP standards |
| [DISTRIBUTED_NONCE_TRACKING.md](DISTRIBUTED_NONCE_TRACKING.md) | Redis-based replay attack prevention |
| [RATE_LIMITING.md](RATE_LIMITING.md) | Brute-force protection implementation |
| [FASTAPI_SECURITY.md](FASTAPI_SECURITY.md) | FastAPI auth/authz patterns |
| [KNOWN_VULNERABILITIES.md](KNOWN_VULNERABILITIES.md) | CVE tracking for dependencies |

## Quick Reference: Critical Fixes Needed

1. **Distributed Nonce Tracking** - Current in-memory storage fails in multi-instance deployments
2. **Rate Limiting** - No protection against brute-force attacks
3. **Token Revocation** - No way to invalidate compromised tokens
4. **Dependency Update** - cryptography>=42.0.4 required (CVE fix)

## Sources

- [OWASP Cheat Sheet Series](https://cheatsheetseries.owasp.org/)
- [Python hmac Documentation](https://docs.python.org/3/library/hmac.html)
- [FastAPI Security Guide](https://fastapi.tiangolo.com/tutorial/security/)
- [NVD - National Vulnerability Database](https://nvd.nist.gov/)
- [PyPI Advisory Database](https://github.com/pypa/advisory-database)

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*Last Updated: 2026-02-08*
