MessagePack is the serializer implementation for Python msgpack.org. Prior to 1.2.1, there is an Out-of-bounds read/crash on Unpacker reuse after a caught error, potentially leading to a DoS attack. If the Unpacker is used repeatedly after an error occurs, the process may crash with a SEGV. This issue has been fixed in version 1.2.1.
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 01 Jul 2026 15:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 01 Jul 2026 10:30:00 +0000

Type Values Removed Values Added
First Time appeared Msgpack
Msgpack msgpack-python
Vendors & Products Msgpack
Msgpack msgpack-python

Tue, 30 Jun 2026 22:15:00 +0000

Type Values Removed Values Added
Description MessagePack is the serializer implementation for Python msgpack.org. Prior to 1.2.1, there is an Out-of-bounds read/crash on Unpacker reuse after a caught error, potentially leading to a DoS attack. If the Unpacker is used repeatedly after an error occurs, the process may crash with a SEGV. This issue has been fixed in version 1.2.1.
Title MessagePack: Out-of-bounds read/crash on Unpacker reuse after caught error
Weaknesses CWE-416
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}


Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-07-01T14:54:36.191Z

Reserved: 2026-06-24T18:49:56.209Z

Link: CVE-2026-57585

cve-icon Vulnrichment

Updated: 2026-07-01T14:54:31.919Z

cve-icon NVD

Status : Analyzed

Published: 2026-06-30T22:16:57.837

Modified: 2026-08-06T15:51:03.847

Link: CVE-2026-57585

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-07-01T10:00:53Z

Weaknesses