Flame authors order infected computers to remove all traces of the malware

Flame self-desctruct module overwrites file data to prevent forensic analysis

The creators of the Flame cyber-espionage threat ordered infected computers still under their control to download and execute a component designed to remove all traces of the malware and prevent forensic analysis, security researchers from Symantec said on Wednesday.

Flame has a built-in feature called SUICIDE that can be used to uninstall the malware from infected computers. However, late last week, Flame's creators decided to distribute a different self-removal module to infected computers that connected to servers still under their control, Symantec's security response team said in a blog post.

The module is called browse32.ocx and its most recent version was created on May 9, 2012. "It is unknown why the malware authors decided not to use the SUICIDE functionality, and instead make Flamer perform explicit actions based on a new module," the Symantec researchers said.

However, even though it is similar in functionality to the SUICIDE feature -- both being able to delete a large number of files associated with the malware -- the new module goes a step further.

"It locates every [Flame] file on disk, removes it, and subsequently overwrites the disk with random characters to prevent anyone from obtaining information about the infection," the Symantec researchers said. "This component contains a routine to generate random characters to use in the overwriting operation. It tries to leave no traces of the infection behind."

Deleting a file in Windows does not remove its actual data from the physical hard disk. It only flags the hard disk sectors occupied by that file as available for the operating system to rewrite.

However, since there is no way to predict when the operating system will actually overwrite those sectors, the deleted file, or portions of it, can be recovered with special data recovery tools -- at least for a limited period of time.

According to Aleks Gostev, chief security expert with Kaspersky Lab's global research & analysis team, the overwriting of file data with meaningless characters happens before the Flame files get deleted by browse32.ocx, not after as Symantec suggested. However, the goal is the same -- eliminating all traces of the malware and making forensic analysis harder, he said via email.

Last week, Kaspersky's researchers said that they discovered Flame while investigating a series of data loss incidents in Iran that could have been caused by a piece of malware. However, no evidence that links Flame to those attacks has been found yet.

Kaspersky's researchers didn't exclude the possibility that a yet-to-be-identified Flame component was responsible for the data destruction in Iran, but if such a component exists, it's probably not browse32.ocx.

"Browse32 does not overwrite the hard disk the way Wiper [the mystery malware] did it," Gostev said. "It wipes only files related to Flame."

Join the newsletter!

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

Edwina Hargreaves

WD My Cloud Home

I would recommend this device for families and small businesses who want one safe place to store all their important digital content and a way to easily share it with friends, family, business partners, or customers.

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

Featured Content

Product Launch Showcase

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?