Bug bounty is not about installing tools and scanning random websites. It is about understanding how web applications are built and identifying where developers make incorrect assumptions.
Before starting, build the following foundations.
1. Web Fundamentals (Non-Negotiable)
You must understand how the web works at a protocol level:
- HTTP and HTTPS
- The request–response lifecycle
- Status codes
- Headers
- Cookies and sessions
- Same-Origin Policy
- CORS
- REST APIs
- JSON
- How authentication flows work
Without strong HTTP knowledge, vulnerability discovery becomes guesswork.
2. Basic Frontend Knowledge
You do not need to be a frontend developer, but you should understand:
- HTML structure
- Basic CSS
- JavaScript fundamentals
- How forms submit data
- How browsers store tokens (cookies, localStorage, sessionStorage)
- How APIs are called from the browser
This knowledge is necessary for identifying:
- Cross-site scripting (XSS)
- DOM-based vulnerabilities
- Token exposure issues
- Client-side logic flaws
3. Backend Understanding (Critical for Real Bounties)
You do not need advanced backend engineering skills, but you must understand:
- Authentication and authorization
- Session management
- JWT structure and validation
- Role-based access control
- Database interaction
- Input validation
- Business logic flow
Learning the basics of one backend stack is enough. Common options include:
- Node.js with Express
- Django
- PHP
You should be capable of building:
- A simple login system
- A protected API endpoint
- Role-based authorization
- A basic database connection
This level of understanding is essential for finding IDOR, access control flaws, and business logic vulnerabilities.
4. Database Basics
You should understand:
- SELECT, INSERT, UPDATE, DELETE
- Basic joins
- How user input is inserted into queries
- The difference between raw queries and ORMs
Database knowledge is required for identifying:
- SQL injection
- Insecure direct object references
- Logic flaws
- Mass assignment issues
5. Linux and Command Line Basics
Most security testing environments are Linux-based. You should be comfortable with:
- File navigation
- grep
- curl
- Basic networking commands
- Understanding system processes
Common environments include:
- Kali Linux
- Ubuntu
6. Core Web Vulnerabilities
Before joining real programs, you must understand:
- XSS (Stored, Reflected, DOM)
- SQL Injection
- CSRF
- IDOR
- SSRF
- Command Injection
- File upload vulnerabilities
- Access control flaws
- Business logic vulnerabilities
Authoritative learning resources include:
- OWASP Top 10
- PortSwigger Web Security Academy
7. Essential Tools
Tools do not replace understanding, but you must be comfortable with:
- Burp Suite
- Nmap
- Fuzzing tools
- Subdomain enumeration tools
Burp Suite is especially important for intercepting, modifying, and analyzing HTTP traffic.
8. Reconnaissance Mindset
Bug bounty is heavily reconnaissance-driven. You must learn:
- Subdomain discovery
- Endpoint discovery
- Parameter fuzzing
- JavaScript file analysis
- API testing methodology
Common platforms to begin with:
- HackerOne
- Bugcrowd
What You Do Not Need Initially
- Expensive certifications
- Advanced reverse engineering
- Deep cryptography knowledge
- OSCP (specifically for starting bug bounty)
Final Perspective
Bug bounty hunting is not about knowing every tool. It is about understanding how web applications are designed and identifying weaknesses in their logic and implementation.
If you can:
- Understand the complete request–response flow
- Recognize how authentication and authorization are implemented
- Think like a developer and test like an attacker
You are ready to begin.