Feeds

Apple QuickTime backdoor creates code-execution peril

Getting punked by 9-year-old parameter

The Power of One eBook: Top reasons to choose HP BladeSystem

A security researcher has unearthed a “bizarre” flaw in Apple's QuickTime Player that can be exploited to remotely execute malicious code on Windows-based PCs, even those running the most recent versions of operating system.

Technically, the inclusion of an unused parameter known as “_Marshaled_pUnk” is a backdoor because it is the work of an Apple developer who added it to to the QuickTime code base and then, most likely, forgot to remove it when it was no longer needed. It sat largely undetected for at least nine years until Ruben Santamarta of Spain-based security firm Wintercore discovered it and realized it could be exploited to take full control of machines running Windows 7, Microsoft's most secure operating system to date.

“The bug is is pretty bizarre,” H D Moore, CSO of Rapid7 and chief architect of the Metasploit project, told The Reg on Monday. “It's not a standard vulnerability in the sense that a feature was implemented poorly. It was more kind of a leftover development piece that was left in production. It's probably an oversight.”

The presence of _Marshaled_pUnk creates the equivalent of an object pointer that an attacker can use to funnel malicious code into computer memory. Over the years, applications have contained so many of these types of errors that Microsoft eventually built architectural designs into Windows that reduced the damage that can be inflicted from attacks that exploit them.

ASLR, or address space layout randomization, for instance, loaded code into memory locations that attackers can't predict, while DEP, or data execution prevention, prevented any code that does get loaded from being executed.

But in a stroke of efficiency, Santamarta figured out how to repurpose code in a common Windows file to bypass the protections. Using a technique known as ROP, short for return oriented programming, he was able to load a Windows Live file known as WindowsLiveLogin.dll into memory and reorder the commands in a way that allowed him to take control of the underlying computer. Using the Microsoft DLL not only allowed him to know where in memory it would load, it also allowed him to get the code executed.

Santamarta said the parameter was present in a QuickTime version dating back to 2001, when it could be used to draw contents into an existing window instead of creating a new one. The functionality was eventually removed from newer versions but the line lived on. Combined with an unrandomized DLL like the one for Windows Live, it represents a serious threat to end users.

The attack has been confirmed on the XP, Vista, and 7 versions of Windows, Santamarta said.

In addition to demonstrating the importance of regular code reviews to identify extraneous parameters, the exploit underscores the threat that comes from programs that fail to use the ASLR and DEP protections baked into more recent versions of Windows. A surprisingly large number of popular applications — including Quicktime, Foxit Reader, Google Picasa, OpenOffice.org, RealPlayer, and VLC Player — all neglect to use one or the other, a recent review by Secunia found.

While the exploit posted by Santamarta works only against those who have Microsoft's Windows Live Messenger installed, the researcher told The Reg that components that ship by default with QuickTime can be used to pull off the same ROP sleight of hand. Files called QuickTimeAuthoring.qtx and QuickTime.qts are two possibilities.

Indeed, programmers with the open-source Metasploit project used by penetration testers and other hackers are in the process of building an attack module that does just that. And that means that in the next 24 hours there will be publicly available exploit code for a critical vulnerability that remains unpatched in Apple's blockbuster media player for Windows.

All because of an obsolete parameter named _Marshaled_pUnk. Go figure. ®

Designing a Defense for Mobile Applications

More from The Register

next story
Secure microkernel that uses maths to be 'bug free' goes open source
Hacker-repelling, drone-protecting code will soon be yours to tweak as you see fit
How long is too long to wait for a security fix?
Synology finally patches OpenSSL bugs in Trevor's NAS
Roll out the welcome mat to hackers and crackers
Security chap pens guide to bug bounty programs that won't fail like Yahoo!'s
HIDDEN packet sniffer spy tech in MILLIONS of iPhones, iPads – expert
Don't panic though – Apple's backdoor is not wide open to all, guru tells us
Researcher sat on critical IE bugs for THREE YEARS
VUPEN waited for Pwn2Own cash while IE's sandbox leaked
Four fake Google haxbots hit YOUR WEBSITE every day
Goog the perfect ruse to slip into SEO orfice
Putin: Crack Tor for me and I'll make you a MILLIONAIRE
Russian Interior Ministry offers big pile o' roubles for busting pro-privacy browser
prev story

Whitepapers

Designing a Defense for Mobile Applications
Learn about the various considerations for defending mobile applications - from the application architecture itself to the myriad testing technologies.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Top 8 considerations to enable and simplify mobility
In this whitepaper learn how to successfully add mobile capabilities simply and cost effectively.
Seven Steps to Software Security
Seven practical steps you can begin to take today to secure your applications and prevent the damages a successful cyber-attack can cause.
Boost IT visibility and business value
How building a great service catalog relieves pressure points and demonstrates the value of IT service management.