diff --git a/test/SemVer.Json.UnitTests/SemVer.Json.UnitTests.csproj b/test/SemVer.Json.UnitTests/SemVer.Json.UnitTests.csproj
index 02067c3..9f4d724 100644
--- a/test/SemVer.Json.UnitTests/SemVer.Json.UnitTests.csproj
+++ b/test/SemVer.Json.UnitTests/SemVer.Json.UnitTests.csproj
@@ -11,7 +11,7 @@
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       <PackageReference Include="JunitXml.TestLogger" Version="8.0.0" />
       <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.8.1" />
-      <PackageReference Include="NSubstitute" Version="5.3.0" />
+      <PackageReference Include="NSubstitute" Version="6.0.0" />
       <PackageReference Include="Verify.Xunit" Version="31.12.5" />
       <PackageReference Include="xunit" Version="2.9.3" />
       <PackageReference Include="xunit.runner.visualstudio" Version="3.1.5">