The day that Microsoft announced Windows RT and that it would be a closed platform, many began to wonder how long it would take for the platform to be jailbroken. While we are still testing the waters ourselves, it looks like the platform has been opened up by vulnerability in the Windows kernel that was ported to the Windows RT platform.
The information comes from a post penned to the Surfsec blog who claims that they have been able to run unsigned desktop applications on Windows RT. Yes, you read that correctly, unsigned desktop applications on Windows RT. The crux of the post is this, there is no technical limitation to stopping desktop applications from running on Windows RT and it appears to be purely a marketing move. We posted the conclusion of the lengthy post explaining the exploit that was used to allow an unsigned desktop application to run on Windows RT:
Windows RT is a clean port of Windows 8. They are the same thing and MSFT enforces Code Integrity to artificially separate these platforms. It does not stop pirates from modifying store apps (and their license checks) because store apps are the only things that can actually run unsigned. The fact that this method works on Windows 8 as well shows how similar the systems are. You can even enforce Code Integrity on Windows 8 to see what Windows RT feels like!
The decision to ban traditional desktop applications was not a technical one, but a bad marketing decision. Windows RT needs the Win32 ecosystem to strengthen its position as a productivity tool. There are enough “consumption” tablets already.
There is a lot to consider as the exploit will only last until you restart the device and it requires quite a few steps to actually unlock and run unsigned code on the platform. But, seeing that, according to the author, the only thing from stopping traditional applications from running on Windows RT is Microsoft blocking the action, it does show the true power of Windows RT.
While we do not know if there is a demand for a home-brew community for the Windows RT platform, iOS arguably became popular after its home-brew community ran wild with the platform and was able to add significant functionality to the device. If Windows RT can develop a serious following, it could be the key to making Microsoft's mobile Windows platform the next billion dollar revenue stream for the company.