Vulnerabilidad · Publicado 22/06/2026 · Actualizado 01/08/2026
MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, when MessagePack-CSharp decompresses Lz4Block or Lz4BlockArray payloads, it reads declared uncompressed lengths from the wire and allocates output buffers based on those lengths before validating that the compressed data is valid or that the declared expansion is reasonable. A small payload can claim a very large un…
MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, when MessagePack-CSharp decompresses Lz4Block or Lz4BlockArray payloads, it reads declared uncompressed lengths from the wire and allocates output buffers based on those lengths before validating that the compressed data is valid or that the declared expansion is reasonable. A small payload can claim a very large uncompressed length and force a large allocation before LZ4 decoding begins. This vulnerability is fixed in 2.5.301 and 3.1.7.
Score: 7.5/10 — Severidad: HIGH — Estado NIST: Analyzed
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Messagepack — Messagepack
CWE-409, CWE-770
Publicado en NIST NVD.