Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Mobile

10/2/2019
03:10 PM
Dark Reading
Dark Reading
Products and Releases
50%
50%

Terrible OpSec Reveals Inner Workings of Hacking Group in Control of Several Million Euros Affecting More than 800,000 People in Russia

Researchers from Czech Technical University, UNCUYO University and Avast dissect the new Geost Android botnet and its handlers at the Virus Bulletin Conference 2019

London, UK – October 2, 2019 – A rare chain of OpSec mistakes led to the discovery of a new Android banking botnet targeting Russian citizens that had been in operation since at least 2016. The Geost botnet, discovered by researchers from Czech Technical University, UNCUYO University, and Avast, infected over 800,000 Android devices (according to researchers’ estimation) and potentially controlled several million Euros. The researchers discovered a more startling story as they began to dissect the unencrypted chat logs found as part of their investigation.

The unusual discovery was made when the botmasters decided to trust a malicious proxy network built using a malware called HtBot. The HtBot malware provides a proxy service that can be rented to give users a pseudo-anonymous communication to the internet. Analysis of the HtBot network communication led to the discovery and disclosure of a large malicious operation infecting more than 800,000 Android-based devices.

In addition to a poor choice of anonymization platform to hide their tracks, the botmasters failed to encrypt their communications, allowing researchers an unprecedented view into their inner workings. The chat logs found revealed how they accessed servers, brought new devices into the botnet, and how they evade antivirus software, but it also contained something more intimate about the social relationships among the botmasters. 

In one conversation, a member of the ring wants to leave the group but the leader encouraged him to stay, saying, “Alexander, really, if we started together we need to finish it. Because for now this is working and we can earn money. Not every day we are getting 100k for promotion.” 

While it is not completely clear what is meant by “promotion,” the leader was also engaged in conversations about money laundering and payments using popular systems among Russian cybercriminals. Further analysis illustrated how the botmasters bring devices into the botnet, and how the delivery of the banking trojan and infiltration of the victim’s banking account follows. 

“We really got an unprecedented view into how an operation like this functions,” said Anna Shirakova, researcher at Avast. “Because this group made some very poor choices in how it tried to hide its actions, we were able to see not just samples of the malware, but also delve deep into how the group works with lower level operatives bringing devices into the botnet and higher level operatives determining how much money was under their control. All told, there were over eight hundred thousand victims and the group potentially controlled millions in currency.”

Geost Botnet and Banking Trojan 

The Geost botnet seems to be a complex infrastructure of infected Android phones. The phones are infected with Android APKs that resemble different fake applications, such as fake banks and fake social networks. Once infected the phones connect to the botnet and are remotely controlled. The usual actions of the attackers seem to be accessing the SMS, sending SMS, communicating with banks, and redirect the traffic of the phone to different sites. The botmasters also access a great deal of personal information from the user.

Following the infection, the command and control stores the complete list of SMS messages of all the victims starting with the moment the device becomes infected. The SMSs were then processed offline in the C&C server to automatically compute the balance of each victim. On subsequent studies, it was possible for the researchers to understand the botmaster’s process for determining which online victims had the largest balance of money. 

The botnet had a complex infrastructure including at least 13 C&C IP addresses, more than 140 domains, and more than 140 APK files. Five banks, mostly from Russia, were the primary targets of the banking trojan, and full details are revealed in the paper of the research. 

Sebastian Garcia, of Czech Technical University, Maria Jose Erquiaga from UNCUYO University, and Anna Shirakova from Avast presented this research at Virus Bulletin 2019 on Wednesday, October 2. The full paper can be found here.

###

-- 

 

Avast logo

     

Leonora Fleming
Public Relations Manager, US
[email protected] | www.avast.com

M: +1.781.974.3549

   

 

Recommended Reading:

Comment  | 
Print  | 
More Insights
Comments
Oldest First  |  Newest First  |  Threaded View
COVID-19: Latest Security News & Commentary
Dark Reading Staff 8/3/2020
Pen Testers Who Got Arrested Doing Their Jobs Tell All
Kelly Jackson Higgins, Executive Editor at Dark Reading,  8/5/2020
New 'Nanodegree' Program Provides Hands-On Cybersecurity Training
Nicole Ferraro, Contributing Writer,  8/3/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Current Issue
Special Report: Computing's New Normal, a Dark Reading Perspective
This special report examines how IT security organizations have adapted to the "new normal" of computing and what the long-term effects will be. Read it and get a unique set of perspectives on issues ranging from new threats & vulnerabilities as a result of remote working to how enterprise security strategy will be affected long term.
Flash Poll
The Changing Face of Threat Intelligence
The Changing Face of Threat Intelligence
This special report takes a look at how enterprises are using threat intelligence, as well as emerging best practices for integrating threat intel into security operations and incident response. Download it today!
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-16248
PUBLISHED: 2020-08-09
** DISPUTED ** Prometheus Blackbox Exporter through 0.17.0 allows /probe?target= SSRF. NOTE: follow-on discussion suggests that this might plausibly be interpreted as both intended functionality and also a vulnerability.
CVE-2020-15820
PUBLISHED: 2020-08-08
In JetBrains YouTrack before 2020.2.6881, the markdown parser could disclose hidden file existence.
CVE-2020-15821
PUBLISHED: 2020-08-08
In JetBrains YouTrack before 2020.2.6881, a user without permission is able to create an article draft.
CVE-2020-15823
PUBLISHED: 2020-08-08
JetBrains YouTrack before 2020.2.8873 is vulnerable to SSRF in the Workflow component.
CVE-2020-15824
PUBLISHED: 2020-08-08
In JetBrains Kotlin before 1.4.0, there is a script-cache privilege escalation vulnerability due to kotlin-main-kts cached scripts in the system temp directory, which is shared by all users by default.