tarteaucitron.js allows prototype pollution via custom text injection

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.5 · CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N

EPSS

• CVE-2025-31475: 0.35% estimated exploitation activity in the next 30 days; percentile 28.85 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

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.

Published by the source

7 Apr 2025, 16:38 UTC

Last modified by the source

7 Apr 2025, 17:42 UTC

Source last checked

26 Oct 2026, 12:36 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-4hwx-xcc5-2hfc

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-4hwx-xcc5-2hfc

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# Patch Next advisory brief: CVE-2025-31475

Advisory: tarteaucitron.js allows prototype pollution via custom text injection
IDs: CVE-2025-31475, GHSA-4hwx-xcc5-2hfc
Record: https://patchnext.com/advisories/cve-2025-31475 (revision 2, source checked 26 Oct 2026, 12:36 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: tarteaucitronjs 1.20.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm tarteaucitronjs: affected < 1.20.1; fixed in 1.20.1

## Suggested inspection (read-only)
- `npm ls tarteaucitronjs --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on tarteaucitronjs.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-4hwx-xcc5-2hfc (OSV record GHSA-4hwx-xcc5-2hfc lists affected ranges: npm tarteaucitronjs >=0 <1.20.1 (fixed))
- Verified: https://github.com/advisories/GHSA-4hwx-xcc5-2hfc (GitHub-reviewed advisory GHSA-4hwx-xcc5-2hfc lists affected ranges: npm tarteaucitronjs >=0 <1.20.1)

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