An intentionally vulnerable e-commerce platform that teaches you to find, exploit, and understand IDOR vulnerabilities — the way they actually appear in the wild.

Let's talk about the most deceptively simple vulnerability in web security: IDOR.

On paper, it sounds trivial — change a number in the URL, access someone else's data, collect your bounty. But anyone who's spent real time hunting knows the truth: IDORs in production applications are rarely that obvious. They hide in request bodies, lurk inside multi-step workflows, and disguise themselves behind modern frontend frameworks that abstract away the very IDs you're supposed to manipulate.

That gap — between textbook IDOR and real-world IDOR — is exactly where IDOR BugBounty Labs lives.

What Is IDOR BugBounty Labs?

It's an open-source, Node.js/Express e-commerce application built with one purpose: to give you a realistic playground for practicing IDOR attacks. Not simulated. Not theoretical. Intentionally vulnerable, locally hosted, and designed to mirror the complexity of actual Bug Bounty targets.

Built with Express and TailwindCSS, it simulates a functioning online store — complete with user accounts, orders, addresses, support tickets, notification settings, and a checkout flow. Every feature contains at least one authorization flaw waiting to be exploited.

Why This Lab Is Different

Most IDOR labs give you one obvious URL parameter to change and call it a day. This one doesn't.

IDOR BugBounty Labs includes:

• 5 distinct challenges ranging from easy to hard
• 3 different IDOR types: URL parameters, request bodies, and hidden body parameters
• Both read and write IDORs — accessing data and modifying it
• Multi-step business logic that mimics real e-commerce flows
• A flag submission system so you can verify your findings

The challenges don't just teach you to change an ID. They teach you to think about where IDs live, how they're passed, and what happens when authorization checks are missing.

The 5 Challenges

1. Read Other Users' Orders

Difficulty: Easy | Type: URL Parameter (Read)

The classic entry point. Login as one user, view your order, and notice the order ID in the URL. Change it. Suddenly you're looking at someone else's purchase history. Simple, but foundational.

2. Delete Other Users' Addresses

Difficulty: Medium | Type: Request Body (Write)

This is where it gets interesting. The vulnerability isn't in the URL — it's in the POST request body. Delete your own address while watching the Network tab, then replay the request with a different address_id. No visual indicator. No obvious parameter. Just a silent, destructive write operation.

3. Download Private Attachments

Difficulty: Hard | Type: URL Parameter (Read)

Support tickets allow file uploads. Each attachment gets a sequential ID. Guess what isn't checked when you request /attachments/download/5? Whether attachment #5 belongs to you. This simulates a real pattern seen in production ticketing systems.

4. Hijack Notification Settings

Difficulty: Medium | Type: Request Body (Write)

Notification preferences are tied to subscription IDs. Update your own, intercept the request, change the subscription_id, and you've just modified another user's email and phone settings. This is the kind of IDOR that doesn't just expose data — it actively harms users.

5. Checkout with Another User's Address

Difficulty: Hard | Type: Hidden Body Parameter (Write)

The crown jewel. During checkout, a shipping_address_id is buried in the POST body. No UI exposes it. No URL hints at it. But if you find it — and change it — you can redirect another user's order to your address. Multi-step, hidden, and devastatingly realistic.

What You'll Actually Learn

This lab doesn't just teach IDOR. It teaches Bug Bounty methodology:

• How to map application flows before testing
• Why you need two accounts (or incognito windows) to test properly
• Where IDs hide in modern SPAs and API-driven apps
• The difference between read and write IDOR impact
• How to use DevTools, Burp Suite, and curl for IDOR hunting
• What makes an IDOR report critical vs. informational

Quick Start

npm install
node app.js

Visit http://localhost:3000 and you're ready to hunt.

Test credentials:

Pro Tips for Hunters

The project README includes some genuinely useful advice:

• Use two browsers or incognito mode to test cross-user access
• Keep the Network tab open at all times
• Look for IDs in JSON bodies, not just URL parameters
• Try both directions when changing IDs — lower and higher
• Check hidden fields, cookies, and headers for embedded references

These aren't just tips for the lab. They're a checklist for every Bug Bounty target you'll ever test.

The Bigger Picture

What makes IDOR BugBounty Labs valuable isn't just the challenges — it's the design philosophy. The creator understands that IDOR isn't one vulnerability; it's a class of authorization failures that manifests differently depending on where the reference lives, how it's transmitted, and what operation it controls.

By the time you've completed all five challenges, you won't just know what IDOR is. You'll have developed the instinct to spot authorization gaps in URL patterns, API payloads, multi-step flows, and hidden parameters — instinct that directly translates to real bounty hunting.

A Note on Ethics

This application is intentionally vulnerable. Keep it on localhost. Don't deploy it publicly. Don't use it for anything other than learning.

The skills you build here are for defending applications and ethically reporting vulnerabilities through proper channels.

Final Thought

The gap between "understanding IDOR" and "finding IDOR in the wild" is wider than most people admit. Labs like this — realistic, challenging, and thoughtfully designed — are how you close it.

If Bug Bounty is your path, IDOR BugBounty Labs belongs in your training rotation.

Explore the lab: GitHub Repository

Author: cyberjson — Instagram | X/Twitter

Happy hunting. Remember: every ID you see is a potential vulnerability — check ownership, always.

Published on Writevo