Feeds

Vista security overhaul questioned

User Account Control: insecure by design?

Beginner's guide to SSL certificates

Security researchers have taken issue with Microsoft's implementation of a security feature in Vista that is designed to stop users from routinely running systems in admin mode.

Users of Windows XP and older Microsoft operating systems habitually ran PCs in admin mode, which gives unrestricted access to the system. As a result, malware attacks carried the ability to take over compromised systems which wouldn't normally be possible if a machine was running in user mode.

The User Account Control (UAC) security functionality of Windows Vista is designed to address this problem by obliging users to run their Vista PCs via a normal user account by default. Users are asked to switch modes and enter login credentials when they request a task requiring admin credentials.

White hat hacker Joanna Rutkowska discovered that users attempting to run an installation file need to do so in admin mode. That means users are confronted with the all-or-nothing choice of granting an installed program complete system privileges or abandoning an installation altogether.

"That means that if you downloaded some freeware Tetris game, you will have to run its installer as administrator, giving it not only full access to all your file system and registry," Rutkowska writes, adding that Win XP gave her the ability to add permissions to her normal (restricted) user account that isn't possible with Vista.

Mark Russinovich, a technical fellow at Microsoft, argues in a detailed response that the design of Vista's User Account Control balances security and usability.

Rutkowska acknowledges that Microsoft has improved the security of its operating system with Vista but warns that the security shortcomings of UAC can not be so easily dismissed. "UAC is not perfect [but that] doesn't diminish the fact that it's a step in the right direction, implementing a least-privilege policy in Windows OS," she writes.

Rutkowska takes issue with Microsoft's contention that flaws in UAC controls don't in themselves create security bugs. She points, by way of example, to a security bug she has discovered which allows a low integrity level process to send WM_KEYDOWN messages to a command prompt window running at high integrity level as among the types of problems she is seeking to highlight. ®

Choosing a cloud hosting partner with confidence

More from The Register

next story
SMASH the Bash bug! Apple and Red Hat scramble for patch batches
'Applying multiple security updates is extremely difficult'
Apple's new iPhone 6 vulnerable to last year's TouchID fingerprint hack
But unsophisticated thieves need not attempt this trick
Hackers thrash Bash Shellshock bug: World races to cover hole
Update your gear now to avoid early attacks hitting the web
Oracle SHELLSHOCKER - data titan lists unpatchables
Database kingpin lists 32 products that can't be patched (yet) as GNU fixes second vuln
Who.is does the Harlem Shake
Blame it on LOLing XSS terroristas
Researchers tell black hats: 'YOU'RE SOOO PREDICTABLE'
Want to register that domain? We're way ahead of you.
Stunned by Shellshock Bash bug? Patch all you can – or be punished
UK data watchdog rolls up its sleeves, polishes truncheon
Ello? ello? ello?: Facebook challenger in DDoS KNOCKOUT
Gets back up again after half an hour though
prev story

Whitepapers

Providing a secure and efficient Helpdesk
A single remote control platform for user support is be key to providing an efficient helpdesk. Retain full control over the way in which screen and keystroke data is transmitted.
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.
Beginner's guide to SSL certificates
De-mystify the technology involved and give you the information you need to make the best decision when considering your online security options.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
Secure remote control for conventional and virtual desktops
Balancing user privacy and privileged access, in accordance with compliance frameworks and legislation. Evaluating any potential remote control choice.