diff --git a/benchmarks/GossipBenchmark/Messages/Messages.csproj b/benchmarks/GossipBenchmark/Messages/Messages.csproj
index ee8d9203f2..2c17102c3d 100644
--- a/benchmarks/GossipBenchmark/Messages/Messages.csproj
+++ b/benchmarks/GossipBenchmark/Messages/Messages.csproj
@@ -4,7 +4,7 @@
     <TargetFramework>net6.0</TargetFramework>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="Google.Protobuf" Version="3.21.0" />
+    <PackageReference Include="Google.Protobuf" Version="3.21.1" />
     <PackageReference Include="Grpc.Tools" Version="2.46.3" PrivateAssets="All" />
     <PackageReference Include="Proto.Cluster.CodeGen" Version="0.30.0" />
   </ItemGroup>
diff --git a/benchmarks/RemoteBenchmark/Messages/Messages.csproj b/benchmarks/RemoteBenchmark/Messages/Messages.csproj
index c069c69e72..abf7c83d53 100644
--- a/benchmarks/RemoteBenchmark/Messages/Messages.csproj
+++ b/benchmarks/RemoteBenchmark/Messages/Messages.csproj
@@ -3,7 +3,7 @@
     <TargetFrameworks>net5.0;net6.0;netcoreapp3.1</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="Google.Protobuf" Version="3.21.0" />
+    <PackageReference Include="Google.Protobuf" Version="3.21.1" />
     <PackageReference Include="System.ValueTuple" Version="4.5.0" />
     <PackageReference Include="Grpc.Tools" Version="2.46.3" PrivateAssets="All" />
   </ItemGroup>
diff --git a/examples/ClusterGrainHelloWorld/Messages/Messages.csproj b/examples/ClusterGrainHelloWorld/Messages/Messages.csproj
index ee8d9203f2..2c17102c3d 100644
--- a/examples/ClusterGrainHelloWorld/Messages/Messages.csproj
+++ b/examples/ClusterGrainHelloWorld/Messages/Messages.csproj
@@ -4,7 +4,7 @@
     <TargetFramework>net6.0</TargetFramework>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="Google.Protobuf" Version="3.21.0" />
+    <PackageReference Include="Google.Protobuf" Version="3.21.1" />
     <PackageReference Include="Grpc.Tools" Version="2.46.3" PrivateAssets="All" />
     <PackageReference Include="Proto.Cluster.CodeGen" Version="0.30.0" />
   </ItemGroup>
diff --git a/examples/ClusterPubSub/ClusterPubSub.csproj b/examples/ClusterPubSub/ClusterPubSub.csproj
index 37e3087f44..a321638dad 100644
--- a/examples/ClusterPubSub/ClusterPubSub.csproj
+++ b/examples/ClusterPubSub/ClusterPubSub.csproj
@@ -10,7 +10,7 @@
     </ItemGroup>
 
     <ItemGroup>
-        <PackageReference Include="Google.Protobuf" Version="3.21.0" />
+        <PackageReference Include="Google.Protobuf" Version="3.21.1" />
         <PackageReference Include="Grpc.Tools" Version="2.46.3">
             <PrivateAssets>all</PrivateAssets>
             <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
diff --git a/examples/ClusterPubSubBatchingProducer/ClusterPubSubBatchingProducer.csproj b/examples/ClusterPubSubBatchingProducer/ClusterPubSubBatchingProducer.csproj
index 3ce0370111..a2de047ce1 100644
--- a/examples/ClusterPubSubBatchingProducer/ClusterPubSubBatchingProducer.csproj
+++ b/examples/ClusterPubSubBatchingProducer/ClusterPubSubBatchingProducer.csproj
@@ -12,7 +12,7 @@
     </ItemGroup>
 
     <ItemGroup>
-        <PackageReference Include="Google.Protobuf" Version="3.21.0" />
+        <PackageReference Include="Google.Protobuf" Version="3.21.1" />
         <PackageReference Include="Grpc.Tools" Version="2.46.3">
             <PrivateAssets>all</PrivateAssets>
             <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
diff --git a/examples/KafkaVirtualActorIngress/KafkaVirtualActorIngress.csproj b/examples/KafkaVirtualActorIngress/KafkaVirtualActorIngress.csproj
index bc0728aa86..973b48ce8c 100644
--- a/examples/KafkaVirtualActorIngress/KafkaVirtualActorIngress.csproj
+++ b/examples/KafkaVirtualActorIngress/KafkaVirtualActorIngress.csproj
@@ -15,7 +15,7 @@
     </ItemGroup>
 
     <ItemGroup>
-      <PackageReference Include="Google.Protobuf" Version="3.21.0" />
+      <PackageReference Include="Google.Protobuf" Version="3.21.1" />
       <PackageReference Include="Grpc.Tools" Version="2.46.3">
         <PrivateAssets>all</PrivateAssets>
         <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
diff --git a/examples/Persistence/Messages/Messages.csproj b/examples/Persistence/Messages/Messages.csproj
index 746ab92844..f2dae2932e 100644
--- a/examples/Persistence/Messages/Messages.csproj
+++ b/examples/Persistence/Messages/Messages.csproj
@@ -3,7 +3,7 @@
     <TargetFramework>netstandard2.1</TargetFramework>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="Google.Protobuf" Version="3.21.0" />
+    <PackageReference Include="Google.Protobuf" Version="3.21.1" />
     <PackageReference Include="System.ValueTuple" Version="4.5.0" />
     <PackageReference Include="Grpc.Tools" Version="2.46.3" PrivateAssets="All" />
   </ItemGroup>
diff --git a/src/Proto.Actor/Proto.Actor.csproj b/src/Proto.Actor/Proto.Actor.csproj
index 96af7f82e9..ad5cd0db4f 100644
--- a/src/Proto.Actor/Proto.Actor.csproj
+++ b/src/Proto.Actor/Proto.Actor.csproj
@@ -8,7 +8,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Google.Protobuf" Version="3.15.0" />
+    <PackageReference Include="Google.Protobuf" Version="3.21.1" />
     <PackageReference Include="Grpc.Tools" Version="2.46.3" PrivateAssets="All" />
     <PackageReference Include="IsExternalInit.System.Runtime.CompilerServices" Version="1.0.0" Condition="'$(TargetFramework)' == 'netstandard2.1'" />
     <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="6.0.0" />