The minimum signing level enforced by Windows RT can be changed by exploiting a vulnerability in the Windows kernel that had existed for some time and is also present in Windows RT, in order to modify that special byte in memory, clrokr said. The default value on x86 machines is of course 0 because you can run anything you like on your computer. "The minimum signing level determines how good an executable's signature is on a scale like this: Unsigned(0), Authenticode(4), Microsoft(8), Windows(12).
"Deep in the kernel, in a hashed and signed data section protected by UEFI's Secure Boot, lies a byte that represents the minimum signing level," clrokr said.
This prevents users from simply taking a desktop application compiled for the ARM architecture and installing it on their Windows RT devices. That said, Windows RT does come with a few preinstalled desktop-enabled applications, like Microsoft Office RT, a special version of Microsoft Office 2013, and Internet Explorer 10.Īccording to clrokr, the restriction of installing only Metro-style apps on Windows RT is enforced through a code integrity mechanism that checks the application's signature before allowing it to be installed.
0 kommentar(er)
