I went to Black Hat over Wednesday and Thursday. The presentation most people wanted to see (including me) was Joanna Rutkowska breaking the Vista x64 driver signing that I hate so much. I wanted to see what trick she’d found. I was let down, however, when she presented her technique.
Her trick was to allocate a bunch of memory so that the kernel pages itself and drivers out, uses raw disk access to overwrite the pagefile, then does an uncommon operation that causes her desired code to execute in kernel mode. Sound familiar? This is the same thing I proposed as a reason why x64 driver signing is pointless when I whined about the real reason for driver signing. I’d already thought of it, so it was nothing new to me, like most of the rest of the conference.
Obviously, Joanna thought of it long before I did, so there is nobody to blame for it. Except, I guess, Microsoft.