Learn Web Application Exploits Defenses Top ((new)): Gruyere

Gruyère is a classic, intentionally vulnerable web application created by Google. It is designed to teach beginners how hackers find flaws and how developers can stop them. It uses a "gray-box" approach, meaning you have access to the source code while you try to break the app.

1. Search for "Google Gruyere" and open the live instance.
2. Complete the 10 core vulnerability units (XSS, CSRF, Path Traversal, etc.).
3. Download the source code and patch three vulnerabilities yourself.
4. Apply the "Gruyere mindset" to your next code review: "If I were an attacker, how would I exploit this line?"

The Exploit: Because cookies are stored on the client side, they can be manipulated. Attackers can modify their own cookies to escalate privileges or impersonate other users. gruyere learn web application exploits defenses top

, the script is saved on the server (e.g., in a user's snippet) and executes when other users view that content. In Reflected XSS Search for "Google Gruyere" and open the live instance