Vulnerability · Published Sep 24, 2025 · Assigned by mitre
CVE-2025-57353
Medium 5.3
In plain English
A medium-severity prototype pollution in the @messageformat/runtime package (npm). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 28% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
The Runtime components of messageformat package for Node.js before 3.0.2 contain a prototype pollution vulnerability. Due to insufficient validation of nested message keys during the processing of message data, an attacker can manipulate the prototype chain of JavaScript objects by providing specially crafted input. This can result in the injection of arbitrary properties into the Object.prototype, potentially leading to denial of service conditions or unexpected application behavior. The vulnerability allows attackers to alter the prototype of base objects, impacting all subsequent object instances throughout the application's lifecycle.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | @messageformat/runtime | 3.0.2 | GHSA-6xv4-9cqp-92rh |
Affected products (as reported)
Weakness: CWE-1321 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
References
- https://github.com/messageformat/messageformat/issues/453
- https://github.com/VulnSageAgent/PoCs/tree/main/JavaScript/prototype-pollution/CVE-2025-57353
- https://github.com/messageformat/messageformat/pull/464
- https://github.com/messageformat/messageformat/commit/82cd10b40e3f922f990bbcf88a6d14b70c0a3ce0
- https://github.com/messageformat/messageformat/issues/453#issuecomment-3466959449