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JSON Web Tokens (JWT4B)


JSON Web Tokens (JWT4B) is used to decode and manipulate JSON web tokens on the fly, checking for their validity and automating common attacks.

Features of JWT4B: - Automatic recognition - JWT Editor - Resigning of JWTs - Signature checks - Automated attacks such as "Alg None" & "CVE-2018-0114" - Validity checks and support for 'expires', 'not before', 'issued at' fields in the payload - Automatic tests for security flags in cookie-transmitted JWTs

Steps to Install

  1. Start Burp Suite.
  2. Navigate to the Extender tab.
  3. Visit the BApp Store.
  4. Search for JSON Web Tokens.
  5. Click Install.

Build Your Own Version with Eclipse

  1. Clone this repository: and create a new Eclipse Java project.
  2. Right-click, go to configure, and click on "Convert to Maven Project."
  3. Open Burp Suite, go to Extender.
  4. Go to APIs and click on "Save files interface". Copy all files to JWT4B\src\burp.
  5. Export a runnable fat JAR including libraries.
  6. Load the JAR in Burp through the Extender Tab -> Extensions -> Click Add.