CVE-2026-107297

medium

Description

msgpack5 is a msgpack v5 implementation for node.js and the browser. Prior to 6.1.0, the streaming decoder reparses an incomplete array or map from the beginning whenever another chunk arrives. A remote peer can split one valid MessagePack container across many small chunks, causing completed elements to be decoded repeatedly, producing quadratic CPU use and blocking the event loop. This issue is fixed in version 6.1.0.

References

https://github.com/mcollina/msgpack5/security/advisories/GHSA-gcx5-hxj7-gpqq

https://github.com/mcollina/msgpack5/releases/tag/v6.1.0

https://github.com/mcollina/msgpack5/commit/e4827641d3105e295cbbd56e9c5389978547eab4

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-95108

Details

Source: Mitre, NVD

Published: 2026-10-08

Updated: 2026-10-08

Risk Information

CVSS v2

Base Score: 5.4

Vector: CVSS2#AV:N/AC:H/Au:N/C:N/I:N/A:C

Severity: Medium

CVSS v3

Base Score: 5.9

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

Severity: Medium

EPSS

EPSS: 0.00389