F-Secure detects aggressive mobile worm variant

A new variant of a Russian mobile worm that uses a couple new tricks has been detected.

Mobile phone malware writers are up to no good again. A security vendor has detected a new variant of an aggressive Russian mobile worm that uses some alarming new tricks.

Like its earlier relatives, Commwarrior.Q will jump onto another phone using a short-range Bluetooth wireless connection, according to Finnish antivirus company, F-Secure. It also spreads via multimedia messaging service (MMS) or by an infected memory card inserted into a device.

Commwarrior.Q is not spreading widely. But the worm has new traits that make it particularly aggressive and it appears to be one of the most complex pieces of mobile malware created to date, vice-president of mobile security for F-Secure, Antti Vihavainen, said

Commwarrior.Q will continuously send MMS messages from midnight to 7 am to people in an infected phone's address book. It cleverly assembles a text message from the phone's sent file, making it appear legitimate, Vihavainen said.

After 7am, however, Commwarrior.Q stops that action, as it would be noticeable to the user. It then starts scanning other phones to infect via Bluetooth. Commwarrior.Q will infect any Symbian OS application installation files, called SIS files. Unlike its predecessors, the SIS files that Commwarrior.Q infects take on random names, making them harder to identify. Previous versions of Commwarrior used the same file name, F-Secure said.

The SIS files also range in size from 32,100 to 32,200 bytes, making them hard to distinguish from MMS messages if mobile operators wanted to filter them out of their networks, Vihavainen said.

Commwarrior.Q couldn't automatically infect a phone, however, Vihavainen said. A user would be prompted if they received an infected SIS file, and they had to accept the file. Users also got another security prompt. After that, however, Commwarrior.Q would start running.

F-Secure had notified mobile operators of the worm, he said. Operators could potentially filter out all transfers of SIS files between phones, but that would reduce functionality.

Commwarrior.Q affects Symbian Series 60 phones that used Symbian OS version 8.1 or older, F-Secure said.

Users may eventually know if they are infected, as Commwarrior.Q intermittently displays an HTML page with text that says, in part, "No panic please, is it very interesting to have mobile virus at own phone."

Commwarrior was first seen in 2005, and several variants have been detected. One version, Commwarrior.B, sends continuous MMSes, draining the phone battery. When charged, the phone won't reboot.

Commwarrior.Q did not damage data on a phone, Vihavainen said. But a user could incur high phone charges caused by the worm sending messages during the night.

Mobile malware is not widespread but researchers say it could become more prevalent as people use more complex mobile devices.

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.

Jeremy Kirk

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

Product Launch Showcase

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?