tarteaucitron.js allows prototype pollution via custom text injection
Date: 2025-04
Affected: npm/tarteaucitronjs
Attack vector: rce
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2025-31475
CWE: CWE-1321
CVSS: 5.5 (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N)

A vulnerability was identified in `tarteaucitron.js`, where the `addOrUpdate` function, used for applying custom texts, did not properly validate input. This allowed an attacker with direct access to the site's source code or a CMS plugin to manipulate JavaScript object prototypes, leading to potential security risks such as data corruption or unintended code execution. ## Impact An attacker with high privileges could exploit this vulnerability to: - Modify object prototypes, affecting core JavaScript behavior, - Cause application crashes or unexpected behavior, - Potentially introduce further security vulnerabilities depending on the application's architecture. ## Fix https://github.com/AmauriC/tarteaucitron.js/commit/74c354c413ee3f82dff97a15a0a43942887c2b5b The issue was resolved by ensuring that user-controlled inputs cannot modify JavaScript object prototypes.


Mitigations:

Architectural layers (MAESTRO):