Yeswiki Vulnerable to Unauthenticated Reflected Cross-site Scripting

Summary

Vulnerable Version: Yeswiki < v4.5.4 Category: Injection CWE: 79: Improper Neutralization of Input During Web Page Generation (CWE-79) CVSS: 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N) Vulnerable Endpoint: /?BazaR Vulnerable Parameter: idformulaire 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

1. Visit the endpoint as mentioned below and see that an alert box pops up: URL with Payload: https://yeswiki.net/?BazaR&vue=formulaire&action=confirm_delete&idformulaire=%3cscript%3ealert(1)%3c%2fscript%3e

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.