/api-security-review

name: api-security-review
description: Comprehensive API security review against OWASP API Security Top 10 (2023). Use when reviewing OpenAPI/Swagger specs, auditing REST/GraphQL/gRPC implementations, testing authentication mechanisms, or checking API gateway configurations. Covers BOLA/IDOR, broken auth, mass assignment, rate limiting, SSRF, and more with real-world attack scenarios.
license: CC-BY-4.0

API Security Review

Perform comprehensive API security assessment following `plays/api-security-review.md`.

Steps

1. **Discovery & Reconnaissance**

• Parse OpenAPI/Swagger specs or scan code for endpoints
• Identify authentication mechanisms (JWT, OAuth 2.0, API keys, mTLS)
• Map API gateway and middleware configurations
• Enumerate all API versions and deprecated endpoints

2. **Authentication Deep Dive**

• JWT security (algorithm confusion, weak signing, token expiration)
• OAuth 2.0 flows (PKCE, state parameter, redirect URI validation)
• API key exposure and rotation policies
• Session management and token storage

3. **Assess All 10 OWASP API Risks** with attack scenarios:

• **API1 BOLA** — IDOR via predictable IDs, batch endpoint bypasses, ownership verification gaps
• **API2 Broken Authentication** — JWT attacks, OAuth flaws, brute force, credential stuffing
• **API3 BOPA** — Mass assignment, response over-exposure, field-level authz bypasses
• **API4 Resource Consumption** — Rate limit bypasses, pagination abuse, GraphQL DoS
• **API5 BFLA** — Admin endpoint discovery, horizontal/vertical privilege escalation
• **API6 Business Flows** — Automated abuse, inventory exhaustion, scraping attacks
• **API7 SSRF** — URL bypasses, DNS rebinding, cloud metadata access
• **API8 Misconfiguration** — CORS bypasses, verbose errors, missing headers
• **API9 Inventory** — Shadow APIs, zombie endpoints, version confusion
• **API10 Unsafe Consumption** — XXE, deserialization, webhook replay attacks

4. **Automated Testing**

• Run API security scanners (OWASP ZAP, Burp Suite, Postman tests)
• Test for common vulnerabilities with specific payloads
• Validate rate limiting and throttling mechanisms

5. **API Gateway & Infrastructure Review**

• Kong, nginx, Envoy, AWS API Gateway configurations
• WAF rules and bypass opportunities
• TLS configuration and certificate validation

Output

Comprehensive API security report including:

• API surface inventory with authentication mechanisms
• Risk matrix with severity ratings for all 10 categories
• Detailed findings with proof-of-concept examples
• Exploit scenarios and business impact analysis
• Prioritized remediation roadmap with code examples
• Testing artifacts and vulnerability evidence

OWASP References

• OWASP API Security Top 10 (2023)
• OWASP ASVS v5.0 — V13: API and Web Service
• OWASP Testing Guide: WSTG-APIT
• OWASP Cheat Sheet: REST Security, GraphQL Security, JWT Security, OAuth 2.0