diff --git a/src/Orchard/Environment/Extensions/Compilers/CSharpExtensionDirectoryCompiler.cs b/src/Orchard/Environment/Extensions/Compilers/CSharpExtensionDirectoryCompiler.cs
index 8a6067be5..3e3d2da99 100644
--- a/src/Orchard/Environment/Extensions/Compilers/CSharpExtensionDirectoryCompiler.cs
+++ b/src/Orchard/Environment/Extensions/Compilers/CSharpExtensionDirectoryCompiler.cs
@@ -4,6 +4,7 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Reflection;
+using System.Security;
 using System.Web.Compilation;
 
 namespace Orchard.Environment.Extensions.Compilers {
@@ -18,6 +19,7 @@ namespace Orchard.Environment.Extensions.Compilers {
             _buildManager = buildManager;
         }
 
+        [SecuritySafeCritical]
         public CompilerResults CompileProject(string location) {
             var codeProvider = CodeDomProvider.CreateProvider("cs");
 
diff --git a/src/Orchard/Environment/Extensions/Compilers/CSharpProjectFullTrustCompiler.cs b/src/Orchard/Environment/Extensions/Compilers/CSharpProjectFullTrustCompiler.cs
index e7473ad51..f770a28d1 100644
--- a/src/Orchard/Environment/Extensions/Compilers/CSharpProjectFullTrustCompiler.cs
+++ b/src/Orchard/Environment/Extensions/Compilers/CSharpProjectFullTrustCompiler.cs
@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Security;
 using Orchard.FileSystems.VirtualPath;
 
 namespace Orchard.Environment.Extensions.Compilers {
@@ -22,6 +23,7 @@ namespace Orchard.Environment.Extensions.Compilers {
         /// Compile a csproj file given its virtual path. Use the CSharp CodeDomProvider
         /// class, which is only available in full trust.
         /// </summary>
+        [SecuritySafeCritical]
         public CompilerResults CompileProject(string virtualPath, string outputDirectory) {
             var codeProvider = CodeDomProvider.CreateProvider("cs");
             var directory = _virtualPathProvider.GetDirectoryName(virtualPath);
diff --git a/src/Orchard/Properties/AssemblyInfo.cs b/src/Orchard/Properties/AssemblyInfo.cs
index e8e04c110..b6b0a9e14 100644
--- a/src/Orchard/Properties/AssemblyInfo.cs
+++ b/src/Orchard/Properties/AssemblyInfo.cs
@@ -37,4 +37,5 @@ using System.Security;
 
 [assembly: AssemblyVersion("0.8.0")]
 [assembly: AssemblyFileVersion("0.8.0")]
-[assembly: SecurityTransparent]
\ No newline at end of file
+[assembly: AllowPartiallyTrustedCallers]
+[assembly: SecurityRules(SecurityRuleSet.Level2)]
\ No newline at end of file