Feeds

Unpatched shortcut vuln exploited by mainstream malware

'Bottom feeders' latch onto zero-day bug

Top 5 reasons to deploy VMware with Tegile

Virus writers have begun using the unpatched shortcut flaw in Windows first exploited by the Stuxnet worm, which targets power plant control systems, to create malware that infects the general population of vulnerable Windows machines.

Slovakian security firm Eset reports the appearance of two malware strains that exploit security vulnerabilities in the way Windows handles .lnk (shortcut) files, first used by Stuxnet to swipe information from Windows-based SCADA systems from Siemens.

The Chymine-A Trojan uses the same security hole to install a keystroke logger while the Autorun-VB-RP worm has been updated to use the shortcut vulnerability as an infection method. The original hackers developed a technique to embed malicious code in shortcut files in such a way that this code is run when an icon is viewed, an approach now followed by less skilled VXers.

Stuxnet featured rootlet functionality and digitally signed malware, techniques that mark it out as highly sophisticated. The latest malware to use the shortcut vulnerability is, by contrast, much more basic.

"The new malware we're seeing is far less sophisticated, and suggests bottom feeders seizing on techniques developed by others," writes Pierre-Marc Bureau, a senior researcher at Eset, in a blog post.

The shortcut vulnerability is likely to become a mainstay of malware distribution techniques, Bureau warns.

"This new development follows a typical path of evolution in malware.  Often there are only days between the initial release of information regarding a critical vulnerability, and the discovery of its exploitation being executed in the wild by malware authors.  It is safe to assume that more malware operators will start using this exploit code in order to infect host systems and increase their revenues," he concludes.

Trend Micro warns that the hole can be exploited by a wide variety of techniques including network shares, malicious websites and booby-trapped Office documents, as well as USB drive infection, the technique associated with the Stuxnet worm.

"File formats that support embedded shortcuts (eg Microsoft Office documents) can now be used to spread exploits as well," writes Trend Micro threat researcher David Sancho. "This means that users who download and open such files could find themselves the latest victim of this vulnerability. It has also been reported that this attack could be used in drive-by attack scenarios, further increasing risks."

Microsoft has issued temporary workarounds and security advice to customers as a stop-gap measure while its security researchers work on developing a fix. The vulnerability involves a security hole in core Windows functionality, so developing and testing a patch by the next scheduled Patch Tuesday, 10 August, will be tricky but not out of the question. Redmond's security team will have had a month by this point to go through a process that more typically takes two months or longer. ®

Top 5 reasons to deploy VMware with Tegile

More from The Register

next story
'Regin': The 'New Stuxnet' spook-grade SOFTWARE WEAPON described
'A degree of technical competence rarely seen'
You really need to do some tech support for Aunty Agnes
Free anti-virus software, expires, stops updating and p0wns the world
You stupid BRICK! PCs running Avast AV can't handle Windows fixes
Fix issued, fingers pointed, forums in flames
Regin: The super-spyware the security industry has been silent about
NSA fingered as likely source of complex malware family
Privacy bods offer GOV SPY VICTIMS a FREE SPYWARE SNIFFER
Looks for gov malware that evades most antivirus
Patch NOW! Microsoft slings emergency bug fix at Windows admins
Vulnerability promotes lusers to domain overlords ... oops
HACKERS can DELETE SURVEILLANCE DVRS remotely – report
Hikvision devices wide open to hacking, claim securobods
prev story

Whitepapers

Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
How to determine if cloud backup is right for your servers
Two key factors, technical feasibility and TCO economics, that backup and IT operations managers should consider when assessing cloud backup.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Getting ahead of the compliance curve
Learn about new services that make it easy to discover and manage certificates across the enterprise and how to get ahead of the compliance curve.