OWASP Juice Shop: A Beginner Bug Bounty Walkthrough

Why Juice Shop Is the Perfect Bounty Training Ground

OWASP Juice Shop is a deliberately vulnerable e-commerce application designed to teach the same vulnerability classes you will find in real bug bounty programs. It has a scoring board, dozens of challenge categories, and it runs entirely on your own machine, so every attack you try is completely legal.

Treat Juice Shop like a real bounty target: write reports as you go, note the request and response for each finding, and rank issues by impact. This habit carries directly into paid bug bounty work on authorized platforms.

As with any target, the golden rule applies here too: only test systems you own or have written permission to test. Juice Shop on your own laptop is yours; a public instance belonging to someone else is not.

docker run --rm -p 3000:3000 bkimminich/juice-shop
# browse to http://localhost:3000 and open the Score Board page

First Steps: Reconnaissance and the Score Board

Start by exploring the application as a normal user. Register an account, browse the catalog, add items to the basket, and place a test order. Every page you visit and every request the browser makes is a clue about the application's structure.

Open the developer tools and watch the network tab. Note the API endpoints the application calls, the authentication flow, and any interesting headers or cookies. This mapping phase is where most good findings are born.

The Score Board page itself is a great orientation tool: it lists every challenge by category, so you can see exactly which vulnerability classes the application contains and track your progress as you solve them.

• •Browse the application as a normal user first
• •Study the API requests in the network tab
• •Open the Score Board and read the challenge names
• •Group challenges by category: injection, XSS, access control, and more

curl -s http://localhost:3000/api/products | head -c 500
# the API is plain JSON - start studying its shape

Finding Your First Bug: Sensitive Data Exposure

One of the gentlest challenges involves sensitive data exposure: sensitive information stored or transmitted in a way that any user can access. In Juice Shop, product reviews and user profiles are a natural place to look, because applications often leak details there that developers assume are protected.

Intercept requests with a proxy and inspect the responses. Look for fields the interface never shows you, like internal IDs, tokens, or personal details. Data that exists in a response is data an attacker can read, even if the UI hides it.

When you find something, prove the impact minimally: show the data is accessible to an unauthenticated or low-privilege user, then stop. That is exactly what a professional bug bounty report looks like.

curl -s http://localhost:3000/api/Products | python3 -m json.tool
# inspect every field in the JSON - hidden fields are often interesting

Injection and Access Control Challenges

Injection challenges in Juice Shop exercise classic flaws like SQL injection and NoSQL injection. Look for places where user input reaches a database query unvalidated: search fields, API parameters, and login forms. A well-crafted payload that changes a query's logic is the classic proof.

Access control challenges ask you to think about authorization, not authentication. Who can see which order? Can you view or modify another user's basket? Can you reach an admin endpoint without admin rights? Test each endpoint with the session of a normal user and watch for what you should not be able to see.

Take notes for every solve: the endpoint, the payload, the request and response, and the impact. These notes become your first self-written walkthrough and a template for future reports.

• •Search for user input that reaches the database
• •Test login and search forms with crafted payloads
• •Test every order, basket, and profile endpoint with another user's context
• •Try to reach admin-only endpoints with a normal session

curl -s "http://localhost:3000/rest/products/search?q='"
# an odd result or a 500 is a signal that input is reaching the query

From Challenges to Real Bounty Skills

Solving Juice Shop challenges is not the end goal; the mindset you build is. The discipline of mapping an application, testing systematically, proving impact, and writing clear reports is exactly what programs pay for.

Write up each solved challenge as if it were a real bounty report: title, affected endpoint, steps to reproduce, impact, and suggested fix. Review your own writeups a week later and see what you would add.

When you feel ready, graduate to authorized bug bounty platforms and real programs on their own infrastructure. Start with low-severity, well-scoped programs and remember the rule that governs everything: only test systems you own or have written permission to test.

mkdir -p reports/juice-shop
# write one markdown report per solved challenge as you go