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Re: bypassing Windows Domain Group Policy Objects
From: James Eaton-Lee <james.mailing () gmail com>
Date: Sat, 29 Apr 2006 01:54:26 +0100

On Thu, 2006-04-27 at 10:37 -0400, Michael Holstein wrote:
Other possible solution, cripple gpupdate.exe (XP) or secedit.exe (2K) 
through permissions (eg: remove 'localsystem:execute'). Deleting them 
will just trigger WFP to replace.

gpupdate and secedit are both just applications that interface with the
Group Policy engine to make changes to the way in which they operate;
the GPE is part of Winlogon, and uses a number of client side extensions
to make changes in the file system, registry, etc. I very much doubt if
denying access to them would prevent group policy from working.

You could attempt to do something with some of the Client Side
Extensions, such as scecli.dll, which is the dll which handles security
settings, but I can't find anyone having done anything similar online;
my guess is that the Group Policy Architecture was designed specifically
to prevent this sort of thing from being easily do-able. 

It might be worthwhile seeing if anyone who spends a lot of time
thinking about lots of this sort of thing within the context of Windows
(such as some of the guys from rootkit.com) has any ideas if you're
particularly interested.

To be honest, if you really wanted to kill group policy, the easiest
thing to do would probably be to just firewall the host in question in
order to prevent any GPOs from being downloaded from the Domain
Controller in the first place.

I may be wrong however - anyone who knows otherwise, please feel free to
enlighten me!

"How Core Group Policy Works"
http://technet2.microsoft.com/WindowsServer/en/Library/eb0042e3-699b-4c49-abcc-e3526dbecc0e1033.mspx has quite a good 
overview of how Group Policy functions.

 - James.

  James (njan) Eaton-Lee | 10807960 | http://www.jeremiad.org
  Semper Monemus Sed Non Audiunt, Ergo Lartus - (Jean-Croix)

sites: https://www.bsrf.org.uk ~ http://www.security-forums.com
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