CVE-2026-48510 (GCVE-0-2026-48510)
Vulnerability from cvelistv5
Published
2026-06-22 21:16
Modified
2026-06-25 15:05
CWE
  • CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Summary
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.
Impacted products
Vendor Product Version
MessagePack-CSharp MessagePack-CSharp Version: >= 3.0, < 3.1.7
Version: < 2.5.301
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Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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