CVE-2026-48517 MessagePack-CSharp: Typeless deserialization type restrictions do not recurse into arrays or generic arguments

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-2026-48517 MessagePack-CSharp: Typeless deserialization type restrictions do not recurse into arrays or generic arguments

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-2026-48517 MessagePack-CSharp: Typeless deserialization type restrictions do not recurse into arrays or generic arguments

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...

dotnet: ASP.NET Core: Denial of Service via uncontrolled resource consumption

A flaw was found in ASP.NET Core SignalR and Blazor Server. A remote attacker could send a specially crafted MessagePack payload containing deeply nested arrays that trigger excessive recursion and cause a stack overflow. This issue may result in application termination and a denial of service...

dotnet: ASP.NET Core: Denial of Service via uncontrolled resource consumption

A flaw was found in ASP.NET Core SignalR and Blazor Server. A remote attacker could send a specially crafted MessagePack payload containing deeply nested arrays that trigger excessive recursion and cause a stack overflow. This issue may result in application termination and a denial of service...

dotnet: ASP.NET Core: Denial of Service via uncontrolled resource consumption

A flaw was found in ASP.NET Core SignalR and Blazor Server. A remote attacker could send a specially crafted MessagePack payload containing deeply nested arrays that trigger excessive recursion and cause a stack overflow. This issue may result in application termination and a denial of service...

PT-2026-51398

Name of the Vulnerable Software and Affected Versions MessagePack for C versions prior to 2.5.301 MessagePack for C versions prior to 3.1.7 Description The UnsafeBlitFormatterBase.Deserialize function reads an attacker-controlled byteLength from an extension payload and allocates an array based o...

PT-2026-51397

Name of the Vulnerable Software and Affected Versions MessagePack for C versions prior to 2.5.301 MessagePack for C versions prior to 3.1.7 Description Runtime-generated union deserializers emitted by DynamicUnionResolver fail to call MessagePackSecurity.DepthStepref reader and do not decrement...

PT-2026-51394

Name of the Vulnerable Software and Affected Versions MessagePack for C versions prior to 2.5.301 MessagePack for C versions prior to 3.1.7 Description When decompressing Lz4Block or Lz4BlockArray payloads, the software reads declared uncompressed lengths from the wire and allocates output buffer...

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...

PT-2026-51400

Name of the Vulnerable Software and Affected Versions MessagePack for C versions prior to 2.5.301 MessagePack for C versions prior to 3.1.7 Description The InterfaceLookupFormatter constructs an internal Dictionary using the default equality comparer instead of the security-aware comparer provide...

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-2026-48502: 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-2026-48515: 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...

PT-2026-51393

Name of the Vulnerable Software and Affected Versions MessagePack for C versions prior to 2.5.301 MessagePack for C versions prior to 3.1.7 Description The parameterless MessagePackInputFormatter constructor uses default serializer options that resolve to MessagePackSerializerOptions.Standard wit...

PT-2026-51396

Name of the Vulnerable Software and Affected Versions MessagePack for C versions prior to 2.5.301 MessagePack for C versions prior to 3.1.7 Description JSON conversion helpers contain multiple recursion paths that do not consistently enforce a depth limit. Specifically, the...

PT-2026-51399

Name of the Vulnerable Software and Affected Versions MessagePack for C versions prior to 2.5.301 MessagePack for C versions prior to 3.1.7 Description Multi-dimensional array formatters read dimension lengths directly from the payload and allocate T,, T,,, or T,,, before validating that the...

PT-2026-51390

Name of the Vulnerable Software and Affected Versions MessagePack for C versions prior to 2.5.301 MessagePack for C versions prior to 3.1.7 Description MessagePack for C is a MessagePack serializer for C. The ReadDateTime function in MessagePackReader can allocate stack memory based on an...