PT-2026-51401 · Messagepack Csharp · Messagepack-Csharp
Published
2026-06-22
·
Updated
2026-06-22
·
CVE-2026-48517
CVSS v4.0
6.3
Medium
| Vector | AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N |
MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, MessagePack-CSharp's typeless deserialization includes MessagePackSerializerOptions.ThrowIfDeserializingTypeIsDisallowed(Type) as a safety check for dangerous types. The default implementation checks the outer type name, but it does not recursively inspect array element types or generic type arguments. As a result, a type that would be blocked directly can be wrapped inside an array or constructed generic type and pass the outer type check. The formatter machinery can then materialize formatters for the inner blocked type. This vulnerability is fixed in 2.5.301 and 3.1.7.
Fix
Deserialization of Untrusted Data
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Related Identifiers
Affected Products
Messagepack-Csharp