diff --git a/dotnet_core/Greeter/GreeterProtos/GreeterProtos.csproj b/dotnet_core/Greeter/GreeterProtos/GreeterProtos.csproj
old mode 100755
new mode 100644
index ce5afb1..a841cd1
--- a/dotnet_core/Greeter/GreeterProtos/GreeterProtos.csproj
+++ b/dotnet_core/Greeter/GreeterProtos/GreeterProtos.csproj
@@ -5,7 +5,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Google.Protobuf" Version="3.0.0" />
+    <PackageReference Include="Google.Protobuf" Version="3.15.0" />
     <PackageReference Include="Grpc" Version="1.0.1" />
     <PackageReference Include="Grpc.Core" Version="1.0.1" />
     <PackageReference Include="Grpc.Tools" Version="1.0.1" />
diff --git a/dotnet_core/Greeter/GreeterServer/GreeterServer.csproj b/dotnet_core/Greeter/GreeterServer/GreeterServer.csproj
old mode 100755
new mode 100644
index 1619196..267da98
--- a/dotnet_core/Greeter/GreeterServer/GreeterServer.csproj
+++ b/dotnet_core/Greeter/GreeterServer/GreeterServer.csproj
@@ -15,7 +15,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Google.Protobuf" Version="3.0.0" />
+    <PackageReference Include="Google.Protobuf" Version="3.15.0" />
     <PackageReference Include="Grpc" Version="1.0.1" />
     <PackageReference Include="Grpc.Core" Version="1.0.1" />
   </ItemGroup>