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CVE-2026-48513 (Low) detected in messagepack.3.1.4.nupkg #48

Description

@mend-bolt-for-github

CVE-2026-48513 - Low Severity Vulnerability

Vulnerable Library - messagepack.3.1.4.nupkg

Extremely Fast MessagePack(MsgPack) Serializer for C# (.NET Framework, .NET 6, Unity, Xamarin).

Library home page: https://api.nuget.org/packages/messagepack.3.1.4.nupkg

Sample Path to Dependency File: /src/SharpConnector.Tests/SharpConnector.Tests.csproj

Path to vulnerable library: /home/wss-scanner/.nuget/packages/messagepack/3.1.4/messagepack.3.1.4.nupkg,/home/wss-scanner/.nuget/packages/messagepack/3.1.4/messagepack.3.1.4.nupkg,/home/wss-scanner/.nuget/packages/messagepack/3.1.4/messagepack.3.1.4.nupkg

Dependency Hierarchy:

  • enyimmemcachedcore.3.5.0.nupkg (Root Library)
    • ❌ messagepack.3.1.4.nupkg (Vulnerable Library)

Found in base branch: main

Vulnerability Details

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.DepthStep(ref reader) and do not decrement reader.Depth around recursive deserialization and skip paths. This means union deserialization does not consistently participate in the maximum object graph depth enforcement that protects other recursive formatter paths. For unknown union keys, the emitted deserializer calls reader.Skip() on attacker-controlled data without an enclosing depth step. This vulnerability is fixed in 2.5.301 and 3.1.7.

Publish Date: 2026-06-22

URL: CVE-2026-48513

CVSS 3 Score Details (3.7)

Base Score Metrics:

  • Exploitability Metrics:
    • Attack Vector: Network
    • Attack Complexity: High
    • Privileges Required: None
    • User Interaction: None
    • Scope: Unchanged
  • Impact Metrics:
    • Confidentiality Impact: None
    • Integrity Impact: None
    • Availability Impact: Low

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Origin: GHSA-wfr3-xj75-pfwh

Release Date: 2026-06-22

Fix Resolution: messagepack - 3.1.7,messagepack - 2.5.301,MessagePack - 2.5.301,MessagePack - 3.1.7


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