diff --git a/source/DefaultUnDo.Test/DefaultUnDo.Test.csproj b/source/DefaultUnDo.Test/DefaultUnDo.Test.csproj
index d7bfa3f..d016f16 100644
--- a/source/DefaultUnDo.Test/DefaultUnDo.Test.csproj
+++ b/source/DefaultUnDo.Test/DefaultUnDo.Test.csproj
@@ -17,7 +17,7 @@
 
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.11.1" />
     <PackageReference Include="NFluent" Version="3.0.4" />
-    <PackageReference Include="NSubstitute" Version="5.1.0" />
+    <PackageReference Include="NSubstitute" Version="5.3.0" />
     <PackageReference Include="xunit" Version="2.9.2" />
 
     <PackageReference Include="System.Threading.Tasks.Extensions" Version="4.5.4" Condition="$(TargetFramework) != 'net8.0'" />