CVE-2026-48506

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, MessagePackReader.TrySkip recursively descends into nested arrays and maps without incrementing the reader depth or calling the configured depth checks. This bypasses MessagePackSecurity.MaximumObjectGraphDepth, the...

CVE-2026-48109

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, A vulnerability exists in the optional LZ4 decompression path used by MessagePack compression modes Lz4Block and Lz4BlockArray. The decoder implementation is based on a deprecated fast-decompression algorithm that do...

CVE-2026-48510

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...

CVE-2026-48513 MessagePack-CSharp: DynamicUnionResolver generated deserializers miss depth enforcement

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, runtime-generated union deserializers emitted by DynamicUnionResolver do not call MessagePackSecurity.DepthStepref reader and do not decrement reader.Depth around recursive deserialization and skip paths. This means...

CVE-2026-48513: Uncontrolled Recursion

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, runtime-generated union deserializers emitted by DynamicUnionResolver do not call MessagePackSecurity.DepthStepref reader and do not decrement reader.Depth around recursive deserialization and skip paths. This means...

CVE-2026-48506: Uncontrolled Recursion

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, MessagePackReader.TrySkip recursively descends into nested arrays and maps without incrementing the reader depth or calling the configured depth checks. This bypasses MessagePackSecurity.MaximumObjectGraphDepth, the...

CVE-2026-48515: Allocation of Resources Without Limits or Throttling

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, MessagePack-CSharp's multi-dimensional array formatters read dimension lengths directly from the payload and allocate T,, T,,, or T,,, before validating that the dimension product matches the encoded element count. T...

CVE-2026-48502: Out-of-bounds Read

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, MessagePackReader.ReadDateTime can allocate stack memory based on an attacker-controlled MessagePack extension length. In the slow path for timestamp extension parsing, the computed tokenSize includes the extension...

CVE-2026-48514: Allocation of Resources Without Limits or Throttling

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, UnsafeBlitFormatterBase .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...

CVE-2026-48510: Improper Handling of Highly Compressed Data (Data Amplification)

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...

CVE-2026-48516: Inefficient Algorithmic Complexity

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, InterfaceLookupFormatter constructs an internal Dictionary with the default equality comparer instead of the security-aware comparer supplied by options.Security.GetEqualityComparer . This formatter omission allows...

CVE-2026-48511: Inefficient Algorithmic Complexity

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, ExpandoObjectFormatter.Deserialize populates System.Dynamic.ExpandoObject by calling IDictionary .Add for each map entry. ExpandoObject internally maintains member names in array-like structures, so inserting many...

CVE-2026-48109: Improper Input Validation

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, A vulnerability exists in the optional LZ4 decompression path used by MessagePack compression modes Lz4Block and Lz4BlockArray. The decoder implementation is based on a deprecated fast-decompression algorithm that do...

CVE-2026-48509: Initialization of a Resource with an Insecure Default

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, the parameterless MessagePackInputFormatter constructor uses default serializer options, which resolve to MessagePackSerializerOptions.Standard with MessagePackSecurity.TrustedData. The formatter is designed for...

CVE-2026-48512: Uncontrolled Recursion

MessagePack for C is a MessagePack serializer for C. Prior to 2.5.301 and 3.1.7, MessagePack-CSharp's JSON conversion helpers contain multiple recursion paths that do not consistently enforce a depth limit. These paths are in the JSON conversion component rather than normal typed MessagePack...

CVE-2026-48517: Use of Externally-Controlled Input to Select Classes or Code

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.ThrowIfDeserializingTypeIsDisallowedType as a safety check for dangerous types. The default implementation checks the outer type nam...

CVE-2020-5234: Stack-based Buffer Overflow

MessagePack for C and Unity before version 1.9.11 and 2.1.90 has a vulnerability where untrusted data can lead to DoS attack due to hash collisions and stack overflow. Review the linked GitHub Security Advisory for more information and remediation steps...