The Burp extension to check JWT (JSON Web Tokens) for using keys from known from public sources. This extension is designed to help security researchers and penetration testers identify potential vulnerabilities in JWT-based applications. It allows you to scan for JWT tokens in HTTP requests and responses, and then analyze them for potential weaknesses. This can help you identify potential vulnerabilities, such as the use of weak keys or predictable salts. This extension is a powerful tool for identifying potential security issues in JWT-based applications. It is a must-have tool for any security researcher or penetration tester working with JWT-based applications.