CVE-2026-57585 (GCVE-0-2026-57585)

Vulnerability from cvelistv5 – Published: 2026-06-30 21:36 – Updated: 2026-07-01 14:54
VLAI
Title
MessagePack: Out-of-bounds read/crash on Unpacker reuse after caught error
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-01 14:54 UTC
CWE
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7690 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
msgpack msgpack-python Affected: < 1.2.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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