{"repo":"AdityaBhatt3010/JWT-Authentication-Bypass-Exploiting-Unverified-Signature-for-Bug-Bounty","free":true,"listed":false,"github":"https://github.com/AdityaBhatt3010/JWT-Authentication-Bypass-Exploiting-Unverified-Signature-for-Bug-Bounty","clone":"git clone https://github.com/AdityaBhatt3010/JWT-Authentication-Bypass-Exploiting-Unverified-Signature-for-Bug-Bounty.git","description":"Exploit a critical JWT flaw to bypass authentication and gain admin access by tampering with an unsigned token payload.","language":null,"stars":13,"topics":["bug-bounty","bugbounty","cybersecurity","jwt","jwt-authentication","jwt-decode","jwt-token"],"license":"MIT","category":"auth-billing-email","readme_excerpt":"🔓 JWT Authentication Bypass: Exploiting Unverified Signature for Bug Bounty Author: Aditya Bhatt Category: Bug Bounty / Web Security / JWT Exploitation Lab: JWT authentication bypass via unverified signature --- 🔍 Introduction JSON Web Tokens (JWTs) are widely used for stateless authentication. They are compact, URL-safe tokens that encapsulate claims used to validate a user’s identity. However, when poorly implemented, they become a prime target for attackers. In this lab from PortSwigger's Web Security Academy, we exploit a critical JWT implementation flaw where the server fails to verify the token’s signature — enabling us to forge arbitrary tokens and impersonate users, including the administrator . --- 🔐 Understanding JWT: A Quick Primer A JWT (JSON Web Token) consists of three base64-encoded parts , separated by dots: 1. Header Specifies metadata, usually the signing algorithm: 2. Payload Contains the actual data (claims), such as user identity or role: 3. Signature Used to verify that the token was not tampered with. It’s generated by hashing the header and payload with a secret key: 📌 If the signature isn’t verified , anyone can change the payload and impersonate users — which is exactly the vulnerability we’ll exploit in this lab. --- 🎯 Lab Objective Exploit the JWT vulnerability to access the /admin panel and delete the user carlos . --- 🛠️ Tools Used Burp Suite PortSwigger Lab JWT Inspector Browser Dev Tools --- ⚙️ Vulnerability Overview This lab uses JWT for","default_branch":null,"files":null,"tree":[],"storefront":"/r/AdityaBhatt3010","claimed":false,"request_supported":{"post":"https://gitbuyer.com/r/AdityaBhatt3010/JWT-Authentication-Bypass-Exploiting-Unverified-Signature-for-Bug-Bounty/request-supported","requests":0},"note":"indexed from public GitHub; nothing is for sale on this page. Clone it from GitHub. Paid listings live at /search."}