CVE-2025-31475: tarteaucitron.js allows prototype pollution via custom text injection

Severity: medium (CVSS 6.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-04-07 · updated 2026-06-17
Weakness: CWE-1321

Description

tarteaucitron.js is a compliant and accessible cookie banner. A vulnerability was identified in tarteaucitron.js prior to 1.20.1, 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. An attacker with high privileges could exploit this vulnerability to modify object prototypes, affecting core JavaScript behavior, cause application crashes or unexpected behavior, or potentially introduce further security vulnerabilities depending on the application's architecture. This vulnerability is fixed in 1.20.1.

Affected products

Amauri Tarteaucitronjs: before 1.20.1 — fixed in 1.20.1

How to fix

Upgrade to a fixed version: Amauri Tarteaucitronjs 1.20.1. Check the vendor advisory for mitigations.

References

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