Defeating Windows Kernel Driver Singing Enforcement, Not That Hard!

04 Nov 2012

These days everybody talks about Driver Signing Enforcement, and the ways we can bypass it. J00ru talked about the hard way, and I tell you about the easy and very long know way. What we need is just a Singed Vulnerable X64 Driver. As we know, loading drivers require administrator privilege, but these days a normal user with default UAC setting can silently achieve Admin privilege without popping up a UAC dialog.

The driver I was talking about is DCR from DriveCrypt. The X64 version is singed and is vulnerable to a write4 bug.

the latest version is not anymore vulnerable but this version still has a valid signature and that’s enough.

I think it's obvious that you can make the whole process of escalating privilege from normal user to Admin for loading vulnerable drive ( silently with one of UAC bypass methods) and exploitation pragmatically automatic.

You can find vulnerable version of drive along the exploit at "DriveCrypt\x64\Release".

This is imported from my old WP blog, some links might be broken, original post.