tarteaucitron.js is a compliant and accessible cookie banner. Prior to 1.33.0, tarteaucitron.cookie.purge() is called on any element with the purgeBtn class and does not check whether the element is a legitimate tarteaucitron button or whether the cookie corresponds to a service handled by tarteaucitron. If an attacker can write HTML with data attributes, an element with data-cookie can silently delete a non-HttpOnly cookie with a known name when clicked by a user. This issue is fixed in version 1.33.0.
https://www.drupal.org/sa-contrib-2026-040
https://github.com/AmauriC/tarteaucitron.js/security/advisories/GHSA-jxj7-g6gm-49j7
https://github.com/AmauriC/tarteaucitron.js/releases/tag/v1.33.0
https://github.com/AmauriC/tarteaucitron.js/commit/24b5464400ae2ff1ad96a092c629b9d632b9cc93