tarteaucitron.js allows UI manipulation via unrestricted CSS injection

A vulnerability was identified in tarteaucitron.js, where user-controlled inputs for element dimensions (width and height) were not properly validated. This allowed an attacker with direct access to the site's source code or a CMS plugin to set values like 100%;height:100%;position:fixed;, potentially covering the entire viewport and facilitating clickjacking attacks.

Impact

An attacker with high privileges could exploit this vulnerability to:

• Overlay malicious UI elements on top of legitimate content,
• Trick users into interacting with hidden elements (clickjacking),
• Disrupt the intended functionality and accessibility of the website.

Fix https://github.com/AmauriC/tarteaucitron.js/commit/25fcf828aaa55306ddc09cfbac9a6f8f126e2d07

The issue was resolved by enforcing strict validation and sanitization of user-provided CSS values to prevent unintended UI manipulation.