Windows PCs remained vulnerable to Stuxnet-like LNK attacks after 2010 patch

A Microsoft patch for an exploit used by the Stuxnet worm was incomplete, researchers found

If you patched your Windows computers in 2010 against the LNK exploit used by Stuxnet and thought you were safe, researchers from Hewlett-Packard have some bad news for you: Microsoft's fix was flawed.

In January, researcher Michael Heerklotz reported privately to HP's Zero Day Initiative (ZDI) that the LNK patch released by Microsoft over four years ago can be bypassed.

This means that over the past four years attackers could have reverse-engineered Microsoft's fix to create new LNK exploits that could infect Windows computers when USB storage devices got plugged into them. However, there's no information yet to suggest this has happened.

The original attack, which exploited a vulnerability in how Windows displayed icons for shortcut (LNK) files, was used to spread Stuxnet, a computer worm that sabotaged uranium enrichment centrifuges at Iran's nuclear facility in Natanz.

Stuxnet, which is believed to have been created by the U.S. and Israel, was discovered in June 2010 after it spread beyond its intended target and ended up infecting tens of thousands of computers around the world. The LNK vulnerability, tracked as CVE-2010-2568, was one of several zero-day, or previously unknown, flaws that Stuxnet exploited. Microsoft patched the flaw in August that same year as part of a security bulletin called MS10-046.

"To prevent this attack, Microsoft put in an explicit whitelist check with MS10-046, released in early August 2010," the HP researchers said in a blog post Tuesday. "Once that patch was applied, in theory only approved .CPL files should have been able to be used to load non-standard icons for links."

"The patch failed," they said. "And for more than four years, all Windows systems have been vulnerable to exactly the same attack that Stuxnet used for initial deployment."

ZDI reported the LNK patch bypass found by Heerklotz to Microsoft, which treated it as a new vulnerability (CVE-2015-0096) and fixed it Tuesday as part of MS15-020. The ZDI researchers plan to examine the new update to see if there are any other possible bypasses.

However, applying the workaround published by Microsoft in 2010, which involves using the registry editor to manually disable the display of icons for shortcut files, will protect against the latest flaw too, they said.

While the LNK attack was first discovered as part of Stuxnet, security researchers from Kaspersky Lab recently found that another computer worm, called Fanny, had used it since 2008. Fanny is part of a malware arsenal used by a highly sophisticated cyberespionage group that Kaspersky has dubbed Equation.

As revealed by a Kaspersky Lab report in August 2014, exploitation of the original CVE-2010-2568 vulnerability remained widespread even after the Microsoft patch in 2010, primarily because the exploit was integrated in more common threats like the Sality worm. From July 2010 to May 2014, Kaspersky Lab detected over 50 million instances of the CVE-2010-2568 exploit on more than 19 million computers worldwide.

Join the newsletter!

Error: Please check your email address.
Rocket to Success - Your 10 Tips for Smarter ERP System Selection

Tags patchesMicrosoftsecurityspywareExploits / vulnerabilitiesmalwarekaspersky lab

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Lucian Constantin

IDG News Service
Show Comments

Cool Tech

SanDisk MicroSDXC™ for Nintendo® Switch™

Learn more >

Breitling Superocean Heritage Chronographe 44

Learn more >

Toys for Boys

Family Friendly

Panasonic 4K UHD Blu-Ray Player and Full HD Recorder with Netflix - UBT1GL-K

Learn more >

Stocking Stuffer

Razer DeathAdder Expert Ergonomic Gaming Mouse

Learn more >

Christmas Gift Guide

Click for more ›

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Walid Mikhael

Brother QL-820NWB Professional Label Printer

It’s easy to set up, it’s compact and quiet when printing and to top if off, the print quality is excellent. This is hands down the best printer I’ve used for printing labels.

Ben Ramsden

Sharp PN-40TC1 Huddle Board

Brainstorming, innovation, problem solving, and negotiation have all become much more productive and valuable if people can easily collaborate in real time with minimal friction.

Sarah Ieroianni

Brother QL-820NWB Professional Label Printer

The print quality also does not disappoint, it’s clear, bold, doesn’t smudge and the text is perfectly sized.

Ratchada Dunn

Sharp PN-40TC1 Huddle Board

The Huddle Board’s built in program; Sharp Touch Viewing software allows us to easily manipulate and edit our documents (jpegs and PDFs) all at the same time on the dashboard.

George Khoury

Sharp PN-40TC1 Huddle Board

The biggest perks for me would be that it comes with easy to use and comprehensive programs that make the collaboration process a whole lot more intuitive and organic

David Coyle

Brother PocketJet PJ-773 A4 Portable Thermal Printer

I rate the printer as a 5 out of 5 stars as it has been able to fit seamlessly into my busy and mobile lifestyle.

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?