API Hacking — Find Vulnerabilities in Modern Applications

API Hacking — The New Frontier

APIs make up 83% of web traffic. They're often less protected than web applications, making them a goldmine for bug bounty hunters.

OWASP API Security Top 10

1. BOLA: Access other users' data via API (most common!)
2. Broken Authentication: Weak tokens, no rate limiting
3. Broken Object Property Level Authorization: Mass assignment
4. Unrestricted Resource Consumption: No rate limits
5. Broken Function Level Authorization: Access admin endpoints
6. Server-Side Request Forgery: SSRF via API parameters
7. Security Misconfiguration: Verbose errors, CORS issues
8. Lack of Protection Against Automated Threats: No bot protection
9. Improper Asset Management: Exposed old API versions
10. Unsafe Consumption of APIs: Trust third-party APIs blindly

API Hacking Techniques

BOLA (Broken Object Level Authorization)

# Change the ID to access other users' data
GET /api/v1/users/123/orders   → Your orders
GET /api/v1/users/124/orders   → Someone else's orders!

Finding Hidden Endpoints

# Fuzz API endpoints
ffuf -u https://api.target.com/FUZZ -w api-wordlist.txt
# Check Swagger/OpenAPI docs
curl https://api.target.com/swagger.json
curl https://api.target.com/docs

Bug Bounty API Payouts

• 🔴 BOLA: $1,000-$20,000
• 🔴 Auth Bypass: $5,000-$50,000
• 🟡 Info Disclosure: $500-$5,000

🔥 Learn API hacking at ONLY4YOU →