700+ Bug Bounty Vulnerabilities: Lessons Learned

Introduction

Over the past few years, I've had the privilege of discovering and reporting over 700 unique security vulnerabilities through various bug bounty platforms. This journey has been both challenging and rewarding, providing invaluable insights into application security and the bug bounty ecosystem.

The Numbers

• Total Vulnerabilities: 700+
• Platforms: HackerOne, Bugcrowd, Inspectiv, and private programs
• Severity Distribution:
  • Critical: 15%
  • High: 35%
  • Medium: 40%
  • Low: 10%

Most Common Vulnerability Types

1. Cross-Site Scripting (XSS) - 25%

XSS remains one of the most prevalent vulnerabilities I encounter:

Reflected XSS Example: ```javascript // Vulnerable code document.write("Hello " + getUrlParameter('name'));

// Payload https://example.com/page?name=<script>alert('XSS')</script> ```

Key Lessons:

• Always check for XSS in error messages
• Look for XSS in less obvious places (headers, cookies, etc.)
• DOM-based XSS is often overlooked by automated scanners

2. SQL Injection - 20%

Despite being well-known, SQL injection vulnerabilities are still common:

```sql -- Vulnerable query SELECT * FROM users WHERE id = '$user_id'

-- Payload 1' UNION SELECT username,password FROM admin_users-- ```

Key Lessons:

• Time-based blind SQL injection is often missed
• Check for SQL injection in JSON parameters
• NoSQL injection is becoming more common

Methodology and Tools

Reconnaissance Phase

1. Subdomain Enumeration ```bash subfinder -d target.com | httpx -title -tech-detect ```

2. Directory Discovery ```bash ffuf -w wordlist.txt -u https://target.com/FUZZ ```

3. Parameter Discovery ```bash arjun -u https://target.com/endpoint ```

Tips for Success

1. Focus on Logic Flaws

Business logic vulnerabilities often have higher impact and bounties.

2. Understand the Application

Spend time understanding how the application works before testing.

3. Automate Repetitive Tasks

Build tools to automate reconnaissance and common vulnerability checks.

4. Stay Updated

Follow security research, new techniques, and vulnerability disclosures.

Conclusion

Discovering 700+ vulnerabilities has been an incredible journey that has shaped my understanding of application security. Each vulnerability taught me something new about security, technology, and the importance of thinking like an attacker.

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This post shares my personal experience in bug bounty hunting. Results may vary, and success requires dedication, skill development, and ethical practices.