Source code for powerful Android banking malware is leaked

More attacks are expected as cybercriminals use the code

The source code for a powerful Android malware program that steals online banking credentials has been leaked, according to researchers with IBM.

The malware family is known by several names, including GM Bot, Slempo, Bankosy, Acecard, Slempo and MazarBot. 

GM Bot has been sold on underground hacking forums for around US$500. But it appears someone who bought the code then leaked it on a forum in December, perhaps to increase his standing, wrote Limor Kessem, a cybersecurity analyst with IBM Trusteer.

The person included an encrypted archive file containing the source code of GM Bot, according to Kessem.

"He indicated he would give the password to the archive only to active forum members who approached him," Kessem wrote. "Those who received the password in turn passed it on to other, unintended users, so the actual distribution of the code went well beyond that discussion board’s member list."

The source code of powerful banking trojans has been leaked before with apps such as Zeus, SpyEye and Carberp, Kessem wrote.

"While GM Bot may not be as prolific as the major banking Trojans mentioned here, it is definitely a game changer in the realm of mobile threats," Kessem added.

GM Bot emerged in late 2014 on Russian-speaking forums. It exploits an issue known as activity hijacking in older Android devices that allow an overlay to be displayed over a legitimate application.

Google has put in defenses against activity hijacking in Android versions higher than 5.0.

The overlay looks like what a user would expect to see after launching a legitimate banking app, but that app is actually running underneath the overlay. The user then inputs their authentication credentials, which are sent to the attackers.

Since GM Bot has full control over the device, it can also steal SMSes, such as one-time authentication codes.

"Previous mobile malware — before overlays became commercially available to fraudsters — could steal SMS codes, but those would have been meaningless without phishing schemes or a trojan on the victim’s PC to steal access credentials," Kessem wrote.

Since the leak of GM Bot's code, it appears its creators have developed a second version "which is sold in financial fraud-themed underground boards," Kessem wrote.

Join the CSO newsletter!

Error: Please check your email address.

More about GoogleTrusteer

Show Comments

Featured Whitepapers

Editor's Recommendations

Solution Centres

Stories by Jeremy Kirk

Latest Videos

  • 150x50

    CSO Webinar: The Human Factor - Your people are your biggest security weakness

    ​Speakers: David Lacey, Researcher and former CISO Royal Mail David Turner - Global Risk Management Expert Mark Guntrip - Group Manager, Email Protection, Proofpoint

    Play Video

  • 150x50

    CSO Webinar: Current ransomware defences are failing – but machine learning can drive a more proactive solution

    Speakers • Ty Miller, Director, Threat Intelligence • Mark Gregory, Leader, Network Engineering Research Group, RMIT • Jeff Lanza, Retired FBI Agent (USA) • Andy Solterbeck, VP Asia Pacific, Cylance • David Braue, CSO MC/Moderator What to expect: ​Hear from industry experts on the local and global ransomware threat landscape. Explore a new approach to dealing with ransomware using machine-learning techniques and by thinking about the problem in a fundamentally different way. Apply techniques for gathering insight into ransomware behaviour and find out what elements must go into a truly effective ransomware defence. Get a first-hand look at how ransomware actually works in practice, and how machine-learning techniques can pick up on its activities long before your employees do.

    Play Video

  • 150x50

    CSO Webinar: Get real about metadata to avoid a false sense of security

    Speakers: • Anthony Caruana – CSO MC and moderator • Ian Farquhar, Worldwide Virtual Security Team Lead, Gigamon • John Lindsay, Former CTO, iiNet • Skeeve Stevens, Futurist, Future Sumo • David Vaile - Vice chair of APF, Co-Convenor of the Cyberspace Law And Policy Community, UNSW Law Faculty This webinar covers: - A 101 on metadata - what it is and how to use it - Insight into a typical attack, what happens and what we would find when looking into the metadata - How to collect metadata, use this to detect attacks and get greater insight into how you can use this to protect your organisation - Learn how much raw data and metadata to retain and how long for - Get a reality check on how you're using your metadata and if this is enough to secure your organisation

    Play Video

  • 150x50

    CSO Webinar: How banking trojans work and how you can stop them

    CSO Webinar: How banking trojans work and how you can stop them Featuring: • John Baird, Director of Global Technology Production, Deutsche Bank • Samantha Macleod, GM Cyber Security, ME Bank • Sherrod DeGrippo, Director of Emerging Threats, Proofpoint (USA)

    Play Video

  • 150x50

    IDG Live Webinar:The right collaboration strategy will help your business take flight

    Speakers - Mike Harris, Engineering Services Manager, Jetstar - Christopher Johnson, IT Director APAC, 20th Century Fox - Brent Maxwell, Director of Information Systems, THE ICONIC - IDG MC/Moderator Anthony Caruana

    Play Video

More videos

Blog Posts

Market Place