CVE-2026-57585

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/msgpack/msgpack-python/commit/2c56ddb5d0025ed481d962c0f5d62d19dec7476d	Patch
https://github.com/msgpack/msgpack-python/security/advisories/GHSA-6v7p-g79w-8964	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:msgpack:messagepack:*:*:*:*:*:python:*:*

History

No history.

Information

Published : 2026-06-30 22:16

Updated : 2026-08-06 15:51

NVD link : CVE-2026-57585

Mitre link : CVE-2026-57585

CVE.ORG link : CVE-2026-57585

JSON object : View

Products Affected

msgpack

messagepack

CWE

CWE-416

Use After Free

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