Re: Remote Windows Kernel Exploitation - Step Into the Ring 0
From: Eirik Schwenke (eirik.schwenke_at_STUDENT.UIB.NO)
Date: Wed, 9 Mar 2005 10:20:46 +0100 To: NTBUGTRAQ@LISTSERV.NTBUGTRAQ.COM
Den 02/17/05 10:00 skrev Marc Maiffret:
> Remote Windows Kernel Exploitation - Step Into the Ring 0
Ah, I love the smell of assembler in the morning ;-p But one thing that struck
me, is (how well) do these exploits work on EMT64/AMD64 windows machines with
the no-exec bit enabled ?
Does anyone on this list know if all kernel code is excepted from NX
restrictions by default ? Because surely a utility-function like the keyboard
buffer, or icmp handler should be read-execute only (ie trying to patch it
should throw an exception of some kind) ?
And if the pages are marked read-only, is it possible to patch the error-handler
for that ?
As the NX handling is toggable, it is obvious that some part of the kernel must
be allowed to change it -- and it sounds reasonable that would mean all kernel
code can change it, due to the NT memory model.
Does anyone have more information on this ?
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