contao : Improper Neutralization of Input During Web Page Generation (Cross-site Scripting) Vulne - CVE-2026-107845

Contao is an Open Source CMS. From version 4.0.0 until 5.3.50 and 5.7.12 an unauthenticated visitor can submit a comment whose email or website metadata is rendered without sufficient attribute and URL encoding by listComments() in comments-bundle/contao/dca/tl_comments.php. When a backend user opens the Comments module attacker-controlled script can execute in the Contao backend origin under that users session. Unpublished comments remain visible to moderators so moderation does not prevent