Penetration Test Your Own App — Before Someone Else Does

The Problem

Your app handles user data. Maybe financial data. Maybe health data. You've never tested it for security vulnerabilities beyond "it works."

Professional pen tests cost $15,000-$50,000. Most startups can't afford them. So they ship with:

• SQL injection in search fields (your database is one ' OR 1=1 -- away from leaking)
• IDOR vulnerabilities (changing user_id=123 to user_id=124 in the URL shows someone else's data)
• Broken authentication (JWT tokens that never expire, password reset tokens that are sequential)
• Missing rate limiting (brute force the login, scrape all data, or DDoS yourself)
• SSRF in URL input fields (internal network scanning through your app)

The Solution

The Penetration Testing skill provides structured testing methodology covering OWASP Top 10, with specific test cases, payloads, and remediation guidance.

The Process

You: Run a pen test methodology against our SaaS app:
- Django REST API backend
- React frontend
- JWT authentication
- PostgreSQL database
- File upload feature
- Stripe payment integration

The agent generates a comprehensive test plan with specific test cases for each OWASP category:

Authentication Testing:

• JWT secret strength (is it "secret123"?)
• Token expiration (do they actually expire?)
• Refresh token rotation (is the old one invalidated?)
• Password reset flow (predictable tokens? rate limited?)
• Account enumeration (does "user not found" vs "wrong password" leak info?)

Authorization Testing (IDOR):

• Change resource IDs in URLs and check if other users' data is accessible
• Test horizontal privilege escalation (user A accessing user B's data)
• Test vertical privilege escalation (regular user accessing admin endpoints)
• Test object-level authorization on every CRUD endpoint

Injection Testing:

• SQL injection on all user input fields
• NoSQL injection (if applicable)
• Command injection on file processing
• SSTI (Server-Side Template Injection)
• XSS (stored, reflected, DOM-based)

File Upload Testing:

• Upload .php/.py/.js files (does the server execute them?)
• Upload oversized files (100MB — does it crash?)
• Upload files with null bytes in filename
• Path traversal in filename (../../../etc/passwd)

Each test includes the specific payload to try, what a vulnerable response looks like, and how to fix it.

The Results

Setup on MrChief

skills:
  - penetration-testing
  - security-audit