diff --git a/backend/test/AcmStatisticsBackend.Tests/AcmStatisticsBackend.Tests.csproj b/backend/test/AcmStatisticsBackend.Tests/AcmStatisticsBackend.Tests.csproj
index c64c5b502..4117d0ebc 100644
--- a/backend/test/AcmStatisticsBackend.Tests/AcmStatisticsBackend.Tests.csproj
+++ b/backend/test/AcmStatisticsBackend.Tests/AcmStatisticsBackend.Tests.csproj
@@ -21,7 +21,7 @@
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     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
-    <PackageReference Include="NSubstitute" Version="4.3.0" />
+    <PackageReference Include="NSubstitute" Version="5.3.0" />
     <PackageReference Include="xunit" Version="2.4.2" />
     <PackageReference Include="xunit.extensibility.execution" Version="2.4.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.5">