diff --git a/dotnet/Directory.Packages.props b/dotnet/Directory.Packages.props
index 76a4444bc1..3f546a3cdf 100644
--- a/dotnet/Directory.Packages.props
+++ b/dotnet/Directory.Packages.props
@@ -21,6 +21,7 @@
     <PackageVersion Include="Aspire.Hosting.Azure.CognitiveServices" Version="$(AspireAppHostSdkVersion)" />
     <PackageVersion Include="Aspire.Microsoft.Azure.Cosmos" Version="$(AspireAppHostSdkVersion)" />
     <PackageVersion Include="CommunityToolkit.Aspire.OllamaSharp" Version="13.0.0" />
+    <PackageVersion Include="MessagePack" Version="3.1.7" /> <!-- Transitive dependency of Aspire pinned to newer version due to vulnerability in 2.5.192 -->
     <!-- Azure.* -->
     <PackageVersion Include="Azure.AI.AgentServer.Core" Version="1.0.0-beta.25" />
     <PackageVersion Include="Azure.AI.AgentServer.Invocations" Version="1.0.0-beta.4" />