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Wanna see how to use Win 7 UAC to pwn a PC?
The Register ^ | 13 January 2009 | John Leyden

Posted on 02/13/2009 2:01:28 PM PST by ShadowAce

White hat hackers have created a proof of concept demo illustrating how improved User Account Control (UAC) features in Windows 7 might be completely bypassed.

The new Win7 UAC code-injection bypass can be used to elevate the rights of any command so that actions, even extreme steps such as thrashing a system, become an option. As such the demo goes beyond previous explorations of how UAC might be simply turned off.

UAC was introduced in Windows Vista as a security feature designed to prompt users for permission before allowing applications to run. Criticised as intrusive and annoying by some, Microsoft is working on a revamped version with increased granularity for Windows 7.

However, Microsoft inadvertently introduced a gaping security hole - disabling UAC no longer generates a prompt. Microsoft initially said this was a design feature but adverse publicity from security researchers forced it to promise it would make alterations.

The importance of these changes is illustrated by new research from Leo Davidson that showed hostile actions beyond simply disabling UAC might be carried out. Davidson's demo is similar to earlier work on how the Windows 7 UAC flaw might be used to silently elevate malware access but goes a step further because it omits ungainly SendKeys or RunDll32 tricks.

Davidson told El Reg that it took him longer to create demonstration videos than to figure out how to turn a "copy a file" concept into a potential "own the machine" technique.

Davidson has created two videos, one showing how Win7's COM elevation works and the second showing "code completely hosing a machine without a UAC prompt" (here).

However security watchers note that the approach only works if prospective victims are tricked into downloading and executing a malicious Trojan package. Achieve that and anything becomes possible.

Thomas Kristensen, CTO at security notification firm Secunia, explained "This isn't a major issue; after all it requires that the user already downloaded some executable code and decided to run it. No matter which security features have been built into the operating system, then the user should never run code, which they don't trust in the first place. Untrusted code should only be run on dedicated test systems."

Secunia has not confirmed the validity of the proof of concept demo but was able to say the demo looked authentic and ought to be addressed before the final version of Windows 7 ships.

"UAC should only be considered an extra security feature, which will remind users that the code they run potentially could harm their systems - it is not meant as a guarantee against code's ability to harm a system," Secunia's Kristensen added. ®


TOPICS: Computers/Internet
KEYWORDS: uac; win7

1 posted on 02/13/2009 2:01:28 PM PST by ShadowAce
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To: rdb3; Calvinist_Dark_Lord; GodGunsandGuts; CyberCowboy777; Salo; Bobsat; JosephW; ...

2 posted on 02/13/2009 2:01:40 PM PST by ShadowAce (Linux -- The Ultimate Windows Service Pack)
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To: ShadowAce

“UAC was introduced in Windows Vista as a security feature designed to prompt users for permission before allowing applications to run. Criticised as intrusive and annoying by some, Microsoft is working on a revamped version with increased granularity for Windows 7.”

That people are now complaining is too lax.

Those people should not be connected to the internet and led should be led away from voting booths.


3 posted on 02/13/2009 2:24:50 PM PST by VanDeKoik (Just another day for you and me in Obama paradise...)
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To: ShadowAce
However security watchers note that the approach only works if prospective victims are tricked into downloading and executing a malicious Trojan package. Achieve that and anything becomes possible.

Of course the only reason to have any kind of protected operating system architecture at all is to prevent a malicious program from succeeding in its mission once it is running on a machine. These engineers have been working on Windows operating systems for so long that they have forgotten that you actually can design and build a secure operating system - one where processes run in a mode with limited access to system resources, and hence the inability to trash the system.

The security problems in Microsoft's products all flow from their poor design and architecture decisions.

4 posted on 02/13/2009 2:39:34 PM PST by freeandfreezing
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To: ShadowAce

People whine if the UAC is on. They whine if the UAC is off.

Back in the 90s, people would whine that Windows lacked certain features. So MS would put in those features. Then folks would whine that MS only put in those features to drive other companies out of business.

So then MS would buy the business and incorporate the features into the operating system. People would then bitch because MS wasn’t writing their own code.

And on and on and on and on.

Fact of the matter is, people just like to bitch.


5 posted on 02/13/2009 3:08:05 PM PST by VeniVidiVici (If the Democrats wish to foist national health care on Americans, give us the same plan Congress has)
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To: ShadowAce
This isn't a major issue; after all it requires that the user already downloaded some executable code and decided to run it.

Or, as the recent fun showed, simply plug in a USB key. Only now UAC can do nothing to protect you from giving the payload access to the entire system.

6 posted on 02/13/2009 3:12:19 PM PST by antiRepublicrat ("I am a firm believer that there are not two sides to every issue..." -- Arianna Huffington)
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To: VeniVidiVici
Fact of the matter is, people just like to bitch.

It is absolutely IMPOSSIBLE to please everyone, so it's not even worth trying.

7 posted on 02/14/2009 6:38:38 PM PST by Born Conservative (Bohicaville: http://bohicaville.wordpress.com/)
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To: ShadowAce
Thomas Kristensen, CTO at security notification firm Secunia, explained "This isn't a major issue; after all it requires that the user already downloaded some executable code and decided to run it. No matter which security features have been built into the operating system, then the user should never run code, which they don't trust in the first place."

Duh, another worthless article from Microsoft bashers.

8 posted on 02/14/2009 8:41:35 PM PST by Golden Eagle (In God We Trust)
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