Wikimedia Foundation MediaWiki Growth Experiments Extension Cross-Site Scripting Vulnerability

A cross-site scripting (XSS) vulnerability has been identified in the Wikimedia Foundation's MediaWiki Growth Experiments Extension, affecting versions 1.39 through 1.43. This vulnerability arises from improper input validation, allowing malicious users to inject harmful scripts that could be executed in the context of the user.

Impact

Exploitation of this vulnerability allows for cross-site scripting, where an attacker can inject malicious scripts that are executed in the context of the user's browser.

Reproduction

To reproduce this vulnerability, visit the Special:Homepage with the parameter ?uselang=x-xss. This will trigger the XSS vulnerability by injecting a script into a message that is not properly escaped, allowing the script to be executed.

Remediation

Users can update to MediaWiki Growth Experiments Extension version 1.44.0 or later, where this vulnerability has been fixed.