The code-optimization feature in the reflection implementation in Microsoft .NET Framework 4 and 4.5 does not properly enforce object permi…

The code-optimization feature in the reflection implementation in Microsoft .NET Framework 4 and 4.5 does not properly enforce object permissions, which allows remote attackers to execute arbitrary code via (1) a crafted XAML browser application (aka XBAP) or (2) a crafted .NET Framework application, aka "WPF Reflection Optimization Vulnerability."