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All labs/skf-jwt-secret

Web

OWASP SKF JWT Weak Secret

A Flask application that issues HS256 JSON Web Tokens at /auth and checks them at /protected. The signing secret is weak.

Not startedDockercommit 0b75c5cx86_64 · aarch64Secret

Objective

Crack the HMAC secret of the token you are issued, then sign a token that identifies you as another user (JWT weak secret).

The brief for this lab lives in its repository.

Submit evidenceSecret

Launch the lab

Open it in the Cyber CTF launcher, or run it yourself with Docker Compose.

Open in the launcher Source code

›Run it manually

$git clone https://github.com/CyberCTF/skf-jwt-secret && cd skf-jwt-secret && docker compose up -d

Without the launcher, the lab uses its public development evidence: great for practice, but it won't complete the lab.

Details

Category: Web
Difficulty: Medium
Evidence: Secret
Runtime: Docker
Runs on: x86_64, aarch64
Commit: 0b75c5c
Repository: CyberCTF/skf-jwt-secret