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__ ke…
Exact source revision recorded 25 Oct 2026 05:17:13 UTC. It does not establish the source's current position. Latest evidence.
nvd · CVE-2026-107301
Publishedmsgpack5 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.
NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.
Source analysis status: Deferred
Weakness classifications: CWE-1321
Original publisher date fields
published: 2026-10-08T17:17:16.143
lastModified: 2026-10-14T01:17:05.583
- Source published
- 8 Oct 2026 17:17:16 UTC
- Source modified
- 14 Oct 2026 01:17:05 UTC
- Observed here
- 25 Oct 2026 05:17:13 UTC
- Source terms
- NIST NVD usage terms; underlying source attribution retained
Original source record · Cite this exact observation · Complete original publisher JSON
This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.
CVSS 3.1 · [email protected] · Secondary · 6.5 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L