If you have recently opened your Firefox web browser you might have noticed a notification from the web browser that the Windows Presentation Foundation plugin was disabled to protect the user and the web browser. Many users who received the message were a bit puzzled as they did not install the plugin in first place. Remember the Microsoft .net Framework Assistant incident earlier this year when Microsoft installed the plugin in the Firefox web browser without notifying the user? The installation of the Windows Presentation Foundation plugin is basically the same deal.

The Windows Presentation Foundation Plugin gets installed when the Microsoft .net Framework 3.5 SP1 gets installed in the Windows operating system. Users who noticed the installation also noticed that they were not able to uninstall the plugin, only disable it in the Firefox plugin manager.

Mozilla today blacklisted the Windows Presentation Foundation Plugin. Not because of the silent install but because of a security vulnerability, or to be precise a remote code execution vulnerability. The vu