msgpack5 is a msgpack v5 implementation for node.js and the browser. Prior to 6.1.0, decoding a negative signed 64-bit integer modifies the corresponding bytes in the caller-provided input buffer while computing the value. Applications that retain or reuse encoded input for integrity checks, logging, or later processing can observe silently corrupted data, while positive integers and other MessagePack value types are unaffected. This issue is fixed in version 6.1.0.
History

Wed, 14 Oct 2026 01:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 09 Oct 2026 09:15:00 +0000

Type Values Removed Values Added
First Time appeared Mcollina
Mcollina msgpack5
Vendors & Products Mcollina
Mcollina msgpack5

Thu, 08 Oct 2026 17:15:00 +0000

Type Values Removed Values Added
Description msgpack5 is a msgpack v5 implementation for node.js and the browser. Prior to 6.1.0, decoding a negative signed 64-bit integer modifies the corresponding bytes in the caller-provided input buffer while computing the value. Applications that retain or reuse encoded input for integrity checks, logging, or later processing can observe silently corrupted data, while positive integers and other MessagePack value types are unaffected. This issue is fixed in version 6.1.0.
Title msgpack5: Decoding negative int64 values mutates the input buffer
Weaknesses CWE-471
References
Metrics cvssV3_1

{'score': 3.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-10-08T17:05:34.059Z

Updated: 2026-10-14T01:01:55.870Z

Reserved: 2026-10-07T15:53:23.587Z

Link: CVE-2026-107296

cve-icon Vulnrichment

Updated: 2026-10-14T01:01:52.050Z

cve-icon NVD

Status : Deferred

Published: 2026-10-08T17:17:15.390

Modified: 2026-10-14T01:17:05.483

Link: CVE-2026-107296

cve-icon Redhat

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