GHSA-cg4f-cq8h-3ch8

### Summary **Vulnerable Version:** Yeswiki < v4.5.4 **Vulnerable Endpoint:** `/?PagePrincipale%2Fdeletepage` **Vulnerable Parameter:** `incomingurl` **Payload:** `"><script>alert(1)</script>`

### Details Reflected Cross-Site Scripting (XSS) attacks are a type of injection, in which malicious scripts are injected into otherwise benign and trusted websites. XSS attacks occur when an attacker uses a web application to send malicious code, generally in the form of a browser-side script, to a different end user. Flaws that allow these attacks to succeed are quite widespread and occur anywhere a web application uses input from a user within the output it generates without validating or encoding it.

### PoC **NOTE:** This vulnerability requires admin access. 1. Visit the endpoint as mentioned below and see that an alert box pops up:

**URL with Payload:** `https://yeswiki.net/?PagePrincipale%2Fdeletepage&incomingurl="><script>alert(1)</script>`

### Impact An attacker can use a reflected cross-site scripting attack to steal cookies from an authenticated user by having them click on a malicious link. Stolen cookies allow the attacker to take over the user’s session. This vulnerability may also allow attackers to deface the website or embed malicious content.