Gruyere Learn Web Application Exploits Defenses Top -

Gruyere teaches that blacklisting (e.g., blocking <script>) fails because attackers use <img src=x onerror=alert()>).

While advanced, Gruyere touches on modern headers. You will learn to send a header like: Content-Security-Policy: script-src 'self' This tells the browser: "Do not execute any inline JavaScript or scripts from external domains." This kills almost all XSS attacks. gruyere learn web application exploits defenses top

Target Layer: Authorization logic
Exploit: User can view or edit another user’s data by changing an ID in the URL or API parameter (IDOR – Insecure Direct Object References). Gruyere teaches that blacklisting (e

Defenses:

The Concept: XSS occurs when an application includes untrusted data in a web page without proper validation or escaping, allowing attackers to execute malicious scripts in a victim’s browser. Gruyere teaches that blacklisting (e.g.