This exercise covers the exploitation of a trivial secret used to sign JWT tokens.

< 1 Hr.
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In this exercise, you will learn to brute-force or guess the secret used to sign JSON Web Tokens (JWT). The integrity of a JWT relies heavily on the strength of its signing secret. If an attacker can discover this secret, they can create malicious tokens. The lab demonstrates how to craft a Python script to brute-force the secret from a given wordlist, allowing you to tamper with JWTs and gain unauthorized access to an admin account.

The practical aspect of the lab involves extracting a JWT from a cookie and using Python to test various secrets until the correct one is found. Once the secret is identified, you can modify the token's payload to assume the identity of an admin user. This exercise highlights the importance of using strong secrets for signing tokens to prevent such attacks.

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