cvedb.io
CVE-2026-48514
HIGH · CVSS 7.5
EPSS exploitation probability: 0%
Published 2026-06-22T22:16:48.230 · Last modified 2026-06-25T16:16:36.300

Summary

MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, UnsafeBlitFormatterBase<T>.Deserialize reads an attacker-controlled byteLength from an extension payload and allocates an array based on that value before validating it against the extension header length or remaining payload bytes. The outer extension header is bounded by available input, but that bound is not used to constrain the inner byteLength before allocation. A very small payload can therefore request a very large T[] allocation. This vulnerability is fixed in 2.5.301 and 3.1.7.

Affected products

messagepack — messagepack

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.