Mobile banking trojans adopt ransomware features

Two Android trojans that steal financial information and login credentials now double as file-encrypting ransomware programs

Cybercriminals are adding file-encrypting features to traditional mobile banking trojans, creating hybrid threats that can steal sensitive information and lock user files at the same time.

One such trojan is called Faketoken and its primary functionality is to generate fake login screens for more than 2,000 financial applications in order to steal login credentials. The malicious app also displays phishing pages to steal credit card information, and it can read and send text messages.

Faketoken's creators have added the ability to encrypt user files stored on the phone's SD card sometime in July and have since released thousands of builds with this functionality, according to researchers from Kaspersky Lab.

"Once the relevant command is received, the Trojan compiles a list of files located on the device (external memory, memory card) corresponding to the given list of 89 extensions and encrypts them," Kaspersky Lab researcher Roman Unuchek said Monday in a blog post. "The AES symmetric encryption algorithm is used, which leaves the user with a chance of decrypting files without paying a ransom."

Faketoken masquerades as popular apps and games and, once installed, it nags the user into giving it the necessary permissions through repeated prompts. It has managed to infect more than 16,000 devices in 27 countries, many of them located in Russia, Ukraine, Germany, and Thailand.

File encryption is not as popular as screen blocking techniques in mobile ransomware because many of the files stored on mobile devices are backed up to cloud services and can be easily restored, according to Unuchek.

That doesn't seem to stop developers from experimenting with such techniques, though. Researchers from security company Comodo have recently analyzed another mobile banking trojan called Tordow 2.0 that has the ability to encrypt files.

Tordow 2.0 contains a pack of exploits that it uses to gain root privileges on infected devices. It is distributed as trojanized versions of popular apps that are available through third-party app stores.

Tordow 2.0 can make telephone calls, control SMS messages, download and install programs, steal login credentials, access contacts, encrypt files, visit web pages, manipulate banking data, remove security software, reboot devices, rename files, and act as ransomware, the Comodo researchers said in a blog post.

Ransomware is a profitable business model for cybercriminals, and the number of file-encrypting programs has exploded this year. A couple of years ago, many observers had doubts that ransomware programs would begin targeting businesses on a large scale because businesses are more likely to have backup procedures in place than consumers.

That didn't stop attackers from trying, and now every 40 seconds, a business is hit by ransomware somewhere in the world. It wouldn't be very surprising to see the number of file-encrypting ransomware programs for mobile devices increase, too, even if mobile phones are more likely to have backups.

Android users should install applications only from the official Google Play store and should make sure that their phones don't allow the installation of apps from unknown sources. It's also a good idea to only download highly rated apps and to read their user reviews.

Join the newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.
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

Toys for Boys

Family Friendly

Stocking Stuffer

SmartLens - Clip on Phone Camera Lens Set of 3

Learn more >

Christmas Gift Guide

Click for more ›

Brand Post

Bitdefender 2019

This Holiday Season, protect yourself and your loved ones with the best. Buy now for Holiday Savings!

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Michael Hargreaves

Microsoft Office 365/Dell XPS 15 2-in-1

I’d recommend a Dell XPS 15 2-in-1 and the new Windows 10 to anyone who needs to get serious work done (before you kick back on your couch with your favourite Netflix show.)

Maryellen Rose George

Brother PT-P750W

It’s useful for office tasks as well as pragmatic labelling of equipment and storage – just don’t get too excited and label everything in sight!

Cathy Giles

Brother MFC-L8900CDW

The Brother MFC-L8900CDW is an absolute stand out. I struggle to fault it.

Luke Hill

MSI GT75 TITAN

I need power and lots of it. As a Front End Web developer anything less just won’t cut it which is why the MSI GT75 is an outstanding laptop for me. It’s a sleek and futuristic looking, high quality, beast that has a touch of sci-fi flare about it.

Emily Tyson

MSI GE63 Raider

If you’re looking to invest in your next work horse laptop for work or home use, you can’t go wrong with the MSI GE63.

Laura Johnston

MSI GS65 Stealth Thin

If you can afford the price tag, it is well worth the money. It out performs any other laptop I have tried for gaming, and the transportable design and incredible display also make it ideal for work.

Featured Content

Product Launch Showcase

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?