Spoofing GUIDs

[TechGrunt]

Hi everyone
I have checked around on google and search this forum but can't find a specific reference to it (which could well be my answer), however this does seem at least theoretically possible.

Has anyone come across an instance of, or know about techniques where a machines GUID can be spoofed? I ask because my organisation is taking steps towards using GUIDs for particular functions and the ability to spoof a GUID would introduce a vulnerability.

Any advice/experiences appreciated.

Regards

TG

[treanglin]

What is a GUID in your case? Can you be more specific?

[The Texan]

Sorry I cant be of much help but i searched under Google and MS.com and as far as i can tell a GUID is UNIQUE so, I dont believe that it can be spoofed of course i have nothing to back this up on since i searched and searched but couldnt find anything to proof otherwise... I mean no technology is foolproof there is always a way to beat it but, I am lead to believe that a GUID presently is truely unique and cant be spoofed... sorry I couldnt be more help but i wanted to give it a shot. goodluck man.

[TechGrunt]

Originally posted here by The Texan
Sorry I cant be of much help but i searched under Google and MS.com and as far as i can tell a GUID is UNIQUE so, I dont believe that it can be spoofed of course i have nothing to back this up on since i searched and searched but couldnt find anything to proof otherwise... I mean no technology is foolproof there is always a way to beat it but, I am lead to believe that a GUID presently is truely unique and cant be spoofed... sorry I couldnt be more help but i wanted to give it a shot. goodluck man.

Thanks for trying Texan. You helped confirmed my nil result search. While not conclusively turning up a "no it can't be done" I think we have determined that it is something that hasn't yet been exploited (possible thing to look forward to I suppose).

Treanglin - In this case I am referring to a GUID as an identifier for a machine on a network.

TG

[@tt!tud3]

2 entries found for GUID.

GUID

\Guid\, n. A flower. See Gold. [Obs.] --Chaucer.

Source: Webster's Revised Unabridged Dictionary, © 1996, 1998 MICRA, Inc.

GUID

GUID: in Acronym Finder

Source: Acronym Finder, © 1988-2004 Mountain Data Systems





this is the best answer i can give... i don't know either that's why i try it in the dictionary

[mohaughn]

Originally posted here by TechGrunt
Thanks for trying Texan. You helped confirmed my nil result search. While not conclusively turning up a "no it can't be done" I think we have determined that it is something that hasn't yet been exploited (possible thing to look forward to I suppose).

Treanglin - In this case I am referring to a GUID as an identifier for a machine on a network.

TG

I think he was asking what type of network, more specifically what type of OS. If you are referring to a Windows 2000/2003 server based network and windows XP clients you would have to find a flaw in their CSP(cryptographic service provider) implementation to spoof a GUID.

The CSP is what generates the GUID and insures that it is authentic for each machine.

It is also possible that someone could compromise a system and extract the GUID from the registry and then apply that guid to another machine. It is stored here-

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Cryptography\MachineGuid

I'm not sure what would happen if both machines were on the network and trying to authenticate to AD at the same time using the same GUID.