Re: [Full-disclosure] [funsec] Vista Protected Processes Bypassed

["C Q" <kyle.c.quest@xxxxxxxxx>]

This is just a common example of sensationalism...
I don't know where this security researcher struck before,
but he definitely didn't strike anything groundbreaking here :-)

This article is misleading... It confuses features
from the 32-bit Vista and from the 64-bit Vista.

It talks about how only signed drivers are suppose to be allowed...
This is only for 64-bits... It doesn't really apply to the 32-bit
version...

The tool that this security researcher released would work
only on the 32-bit version because it actually hides a simple
driver in the executable. First, it calls RtlAdjustPrivilege
to be able to install a driver (meaning that if you don't
have admin priviledges it's not gonna work). Then it
drops its hidden driver calling RtlDecompressBuffer,
creating a hidden alternative data stream in the crusoe.sys
driver. Next it sets up a registry entry for this hidden driver
and calls NtLoadDriver. The driver itself simply grabs
the process id (passed by the user through what seems
to be the KUSER_SHARED_DATA region), calls
PsLookupProcessByProcessId(pid,&pEprocess), and if the call is successful
it simply clears the 'ProtectedProcess' flag
(pEprocess->Flags2.ProtectedProcess = 0).

This is the same approach used to unlock files that were
open for exclusive I/O operations... you go into the kernel
finding the corresponding data structure and then set the bit
that prevents you from accessing your target :-)

This wouldn't work if the driver really needed to be signed
(which would be the case for the 64-bit version of Vista) unless
somebody finds an exploit to load unsigned code.

Overall, it's not really worse than what you'd have with XP...
I'm not a big fan of Vista, but this is definitely not what
people make it to be.

Kyle

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