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.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://github.com/msgpack/msgpack-python/commit/2c56ddb5d0025ed481d962c0f5d62d19dec7476d Patch
- https://github.com/msgpack/msgpack-python/security/advisories/GHSA-6v7p-g79w-8964 Mitigation, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 7.5 · msgpackNVD modified 2026-10-25 21:10
Affected (CPE criteria) 1
cpe:2.3:a:msgpack:messagepack:*:*:*:*:*:python:*:*