Description


msgpack5 is a msgpack v5 implementation for node.js and the browser. Prior to 6.1.0, constructing msgpack5 with an empty or partial options object disables the default protoAction: 'error' protection. A decoded map containing a __proto__ key can then replace the decoded object's prototype, potentially changing inherited properties or downstream behavior, although Object.prototype is not modified globally. This issue is fixed in version 6.1.0.

Related CPE's


Could not find any relations

Weaknesses



CWE-1321

CVSS impact metrics


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

6.5 · Medium

Information


Source identifier

[email protected]

Vulnerability status

Deferred

Published

2026-10-08T17:17:16.143Z

15 hours ago

Last modified

2026-10-08T20:48:36.970Z

12 hours ago