diff --git a/CHANGELOG.md b/CHANGELOG.md
index 406821a0f..a580525ca 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,20 @@ All notable changes to this project will be documented in this file.
 The format is loosely based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 
 
+## Unreleased
+
+New major version of DynamicProxy (you may get better performance!), so please update with care.
+
+#### Changed
+
+* Update package reference to `Castle.Core` (DynamicProxy) from version 4.4.1 to 5.0.0 (@stakx, #1257)
+
+#### Fixed
+
+* Can't set up "private protected" properties (@RobSiklos, #1170)
+* Using [...] an old version of `System.Net.Http` which is vulnerable to "DoS", "Spoofing", "Privilege Escalation", "Authentication Bypass" and "Information Exposure"  (@sidseter, #1219)
+
+
 ## 4.17.2 (2022-03-06)
 
 #### Fixed
diff --git a/appveyor.yml b/appveyor.yml
index 1ad292254..3a3f24f4b 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,4 +1,4 @@
-image: Visual Studio 2019
+image: Visual Studio 2022
 
 init:
   - git config --global core.autocrlf input
diff --git a/src/Moq/Moq.csproj b/src/Moq/Moq.csproj
index 1976ecaca..6ac1a5f65 100644
--- a/src/Moq/Moq.csproj
+++ b/src/Moq/Moq.csproj
@@ -6,20 +6,20 @@
 	<Import Project="$(BuildDirectory)SourceLink.props" />
 
 	<PropertyGroup>
-		<TargetFrameworks>net45;netstandard2.0;netstandard2.1</TargetFrameworks>
+		<TargetFrameworks>net462;netstandard2.0;netstandard2.1;net6.0</TargetFrameworks>
 		<AssemblyName>Moq</AssemblyName>
 		<DebugSymbols>True</DebugSymbols>
 		<DebugType>embedded</DebugType>
 		<DocumentationFile>bin\$(Configuration)\$(TargetFramework)\$(AssemblyName).xml</DocumentationFile> 
 		<GenerateDocumentation>true</GenerateDocumentation>
-		<NoWarn>0419</NoWarn>
+		<NoWarn>$(NoWarn);0419;CS8032</NoWarn>
 		<RootNamespace>Moq</RootNamespace>
 		<TreatWarningsAsErrors>true</TreatWarningsAsErrors>
 		<WarningLevel>4</WarningLevel>
 		<LangVersion>9.0</LangVersion>
 	</PropertyGroup>
 
-	<PropertyGroup Condition=" '$(TargetFramework)' == 'netstandard2.1' ">
+	<PropertyGroup Condition=" '$(TargetFramework)' == 'netstandard2.1' Or '$(TargetFramework)' == 'net6.0' ">
 		<DefineConstants>$(DefineConstants);FEATURE_DEFAULT_INTERFACE_IMPLEMENTATIONS</DefineConstants>
 	</PropertyGroup>
 
@@ -43,7 +43,7 @@
 	</PropertyGroup>
 
 	<ItemGroup>
-		<PackageReference Include="Castle.Core" Version="4.4.1" />
+		<PackageReference Include="Castle.Core" Version="5.0.0" />
 		<PackageReference Include="IFluentInterface" Version="2.1.0" PrivateAssets="All" />
 		<PackageReference Include="Microsoft.NETFramework.ReferenceAssemblies" Version="1.0.0" PrivateAssets="All" />
 		<PackageReference Include="System.Threading.Tasks.Extensions" Version="4.5.4" />
diff --git a/tests/Moq.Tests.FSharpTypes/Moq.Tests.FSharpTypes.fsproj b/tests/Moq.Tests.FSharpTypes/Moq.Tests.FSharpTypes.fsproj
index 85733a51d..8f94e9f5b 100644
--- a/tests/Moq.Tests.FSharpTypes/Moq.Tests.FSharpTypes.fsproj
+++ b/tests/Moq.Tests.FSharpTypes/Moq.Tests.FSharpTypes.fsproj
@@ -4,7 +4,7 @@
 	<Import Project="$(BuildDirectory)SignAssembly.props" />
 
 	<PropertyGroup>
-		<TargetFrameworks>net472;netcoreapp3.1</TargetFrameworks>
+		<TargetFrameworks>net472;netcoreapp3.1;net6.0</TargetFrameworks>
 		<DebugSymbols>True</DebugSymbols>
 		<DebugType>portable</DebugType>
 		<IsPackable>False</IsPackable>
diff --git a/tests/Moq.Tests.VisualBasic/Moq.Tests.VisualBasic.vbproj b/tests/Moq.Tests.VisualBasic/Moq.Tests.VisualBasic.vbproj
index 0d900436f..4f84c0d04 100644
--- a/tests/Moq.Tests.VisualBasic/Moq.Tests.VisualBasic.vbproj
+++ b/tests/Moq.Tests.VisualBasic/Moq.Tests.VisualBasic.vbproj
@@ -5,7 +5,7 @@
 	<Import Project="$(BuildDirectory)xUnit.props" />
 
 	<PropertyGroup>
-		<TargetFrameworks>net472;netcoreapp3.1</TargetFrameworks>
+		<TargetFrameworks>net472;netcoreapp3.1;net6.0</TargetFrameworks>
 		<DebugSymbols>True</DebugSymbols>
 		<DebugType>portable</DebugType>
 		<IsPackable>False</IsPackable>
diff --git a/tests/Moq.Tests/Moq.Tests.csproj b/tests/Moq.Tests/Moq.Tests.csproj
index 6ca49cc95..9ce9ab910 100644
--- a/tests/Moq.Tests/Moq.Tests.csproj
+++ b/tests/Moq.Tests/Moq.Tests.csproj
@@ -5,24 +5,25 @@
 	<Import Project="$(BuildDirectory)xUnit.props" />
 
 	<PropertyGroup>
-		<TargetFrameworks>net472;netcoreapp3.1</TargetFrameworks>
+		<TargetFrameworks>net472;netcoreapp3.1;net6.0</TargetFrameworks>
 		<AssemblyName>Moq.Tests</AssemblyName>
 		<DebugSymbols>True</DebugSymbols>
 		<DebugType>portable</DebugType>
 		<GenerateRuntimeConfigurationFiles>true</GenerateRuntimeConfigurationFiles>
 		<LangVersion>8.0</LangVersion>
 		<IsPackable>False</IsPackable>
+		<NoWarn>$(NoWarn);CS8032</NoWarn>
 	</PropertyGroup>
 
 	<PropertyGroup Condition=" '$(TargetFramework)' == 'net472' ">
 		<DefineConstants>$(DefineConstants);FEATURE_DYNAMICPROXY_SERIALIZABLE_PROXIES;FEATURE_EF;FEATURE_SYSTEM_WEB;FEATURE_SYSTEM_WINDOWS_FORMS</DefineConstants>
 	</PropertyGroup>
-	<PropertyGroup Condition=" '$(TargetFramework)' == 'netcoreapp3.1' ">
+	<PropertyGroup Condition=" '$(TargetFramework)' == 'netcoreapp3.1' Or '$(TargetFramework)' == 'net6.0' ">
 		<DefineConstants>$(DefineConstants);FEATURE_DEFAULT_INTERFACE_IMPLEMENTATIONS</DefineConstants>
 	</PropertyGroup>
 
 	<ItemGroup>
-		<PackageReference Include="Castle.Core" Version="4.4.1" />
+		<PackageReference Include="Castle.Core" Version="5.0.0" />
 		<PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="3.1.9" />
 		<PackageReference Include="Microsoft.NETFramework.ReferenceAssemblies" Version="1.0.0" PrivateAssets="All" />
 		<PackageReference Include="System.ValueTuple" Version="4.5.0" />
diff --git a/tests/Moq.Tests/Regressions/IssueReportsFixture.cs b/tests/Moq.Tests/Regressions/IssueReportsFixture.cs
index 88d3a8647..428615aef 100644
--- a/tests/Moq.Tests/Regressions/IssueReportsFixture.cs
+++ b/tests/Moq.Tests/Regressions/IssueReportsFixture.cs
@@ -970,7 +970,6 @@ public void strict_mock_accepts_null_as_nullable_guid_value()
 
 		public class Issue193
 		{
-			[Fact(Skip = "Fails due to a bug in Castle DynamicProxy. Try enabling this test once we reference Castle.Core > 4.4.0.")]
 			public void Can_mock_class_type_where_generic_type_parameter_name_diverges_from_name_in_interface()
 			{
 				var mock = new Mock<C>();