CVE-2026-48514 (GCVE-0-2026-48514)
Vulnerability from cvelistv5
Published
2026-06-22 21:11
Modified
2026-06-25 15:23
CWE
  • 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, 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.
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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