The world of bug bounty hunting is both exciting and rewarding. Platforms like HackerOne, Bugcrowd, and Synack are constantly looking for fresh minds to help secure the digital frontier. If you’re just starting out, the first step is understanding which vulnerabilities are easiest to learn, find, and exploit — legally and ethically.

In this article, we’ll explore 5 beginner-friendly vulnerabilities:

1. IDOR (Insecure Direct Object Reference)

2. XSS (Cross-Site Scripting)

3. Security Misconfigurations

4. Sensitive Data Exposure

5. Open Redirect

Let’s deep dive into each one — what it is, how it works, and how to hunt it using tools and methods that both professionals and beginners can use.

1. 🔓 Insecure Direct Object Reference (IDOR)

🔍 What is IDOR?

IDOR occurs when applications expose internal object references (like user IDs, document IDs) without proper access control.

🧠 How It Works

If https://example.com/profile?user_id=123 shows your profile and you change 123 to 124 and see someone else’s profile, that’s an IDOR vulnerability.

🧰 Tools & Techniques

• Burp Suite (Community/Pro) — Use the Repeater tab to manipulate request parameters.

• Browser DevTools — Inspect API calls and URLs.

• Fuzzer (Burp Intruder, ffuf) — Automate testing for sequential IDs.

✅ How to Hunt

1. Find endpoints exposing IDs or tokens.

2. Intercept the request in Burp Suite.

3. Modify the ID value.

4. Check for unauthorized access or data leakage.

💡 Pro Tip:

Look for endpoints like /download?id=, /order?id=, /invoice?id=, etc.

2. 🖊️ Cross-Site Scripting (XSS)

🔍 What is XSS?

XSS lets attackers inject malicious scripts into websites viewed by others.

🧠 How It Works

If a comment box lets you post <script>alert('XSS')</script> and it gets executed, it's a classic stored XSS.

🧰 Tools & Techniques

• Burp Suite

• XSS Hunter — Track blind XSS.

• XSStrike — Open-source XSS scanner.

✅ How to Hunt

1. Find input fields like search, contact forms, comment boxes.

2. Try payloads like:

• <script>alert('1')</script>

• "><img src=x onerror=alert(1)>

3. Observe if the script executes or if HTML is reflected back.

4. Use Burp Repeater or Proxy to tweak payloads.

💡 Pro Tip:

Try encoding and bypass filters using tools like HackBar browser extension.

3. 🧱 Security Misconfigurations

🔍 What is it?

These are incorrect server or app settings that leak information or allow unsafe operations.

🧠 How It Works

If a site exposes .git/, phpinfo(), or has default admin credentials, that’s a misconfiguration.

🧰 Tools & Techniques

• WhatWeb — Fingerprints web technologies.

• Nikto — Scans for common misconfigurations.

• Wappalyzer — Chrome/Firefox plugin for tech stack info.

✅ How to Hunt

1. Check for accessible admin panels (/admin, /wp-admin).

2. View response headers: look for unnecessary disclosure (e.g., X-Powered-By: PHP/7.4.1).

3. Use WhatWeb to discover version info.

4. Visit common endpoints: /robots.txt, /config, /backup.

💡 Pro Tip:

Search for exposed .env or .git/config files on public servers.

4. 🔐 Sensitive Data Exposure

🔍 What is it?

When apps fail to protect data like passwords, API keys, or tokens — either in transit or at rest.

🧠 How It Works

You find sensitive info in browser storage, API responses, error messages, or JavaScript files.

🧰 Tools & Techniques

• Burp Suite

• FindSecrets (GitHub scanner)

• Grep/Strings command in Linux

✅ How to Hunt

1. Monitor responses for secrets using Burp Logger.

2. Explore JavaScript files — search for apiKey, token, auth, etc.

3. Use GitHub dorking:
   site:github.com api_key filename:.env

💡 Pro Tip:

Use tools like shhgit or truffleHog to scan leaked secrets in public repos.

5. 🔁 Open Redirect

🔍 What is it?

Open Redirect allows an attacker to redirect users to a malicious website by modifying URLs.

🧠 How It Works

If a URL like
https://example.com/login?redirect=https://evil.com
redirects you to evil.com after login — that’s a vulnerability.

🧰 Tools & Techniques

• Burp Suite

• Open Redirect Payload Lists (PayloadAllTheThings)

• Manual URL tampering

✅ How to Hunt

1. Look for ?next=, ?url=, ?redirect= parameters.

2. Change them to:

• https://google.com

• //evil.com

• //example.com@evil.com

See if the app redirects without validation.

💡 Pro Tip:

Report chained attacks like phishing with open redirect — these often have higher bounty value.

🧭 Getting Started on a Bug Bounty Platform

👣 Step-by-Step Guide:

1. Create accounts on: HackerOne, Bugcrowd, Synack (invite-based), Intigriti.

2. Start with public programs — they allow beginners.

3. Read scope carefully — respect the rules, don’t test production login with brute force.

4. Maintain a report template — include:

• Summary

• Steps to reproduce

• Impact

• Screenshots/Payloads

• — -> Always stay ethical and legal. Use responsible disclosure practices.

🎥 Top 6 Beginner-Friendly YouTube Channels to Learn Bug Bounty (Hindi + English)

1. Technical Suneja (Hindi)

2. TheCyberMentor (English)

3. Ankit Fadia (Hindi + English)

4. STOK (English)

5. Hacker Bro (Hindi)

6. ehackopedia (Hindi)

🧠 Final Thoughts

Starting bug bounty hunting can feel overwhelming. But by mastering these five beginner-friendly vulnerabilities, you’ll gain:

• Real-world hacking skills

• Confidence to contribute to security

• A shot at earning your first bounty

🔐 Remember:

“You don’t need to hack NASA on Day 1. Just find one good bug, and you’re in the game.”