Incidents

The first Tor Trojan for Android

Virus writers of Android Trojans have traditionally used Windows malware functionality as a template. Now, yet another technique from Windows Trojans has been implemented in malware for Android: for the first time we have detected an Android Trojan that uses a domain in the .onion pseudo zone as a C&C. The Trojan uses the anonymous Tor network built on a network of proxy servers. As well as providing users with anonymity, Tor makes it possible to display ‘anonymous’ sites in the .onion domain zone that can only be accessed in Tor.

tor_backdoor_01s

Backdoor.AndroidOS.Torec.a is a variation of the popular Orbot Tor client. The cybercriminals have added their own code to the application, though the Trojan doesn’t pass itself off as Orbot – it simply uses the functionality of the client.

tor_backdoor_02s

The Trojan can receive the following commands from the C&C:

tor_backdoor_03s

  • start/stop intercepting incoming SMSs
  • start/stop theft of outgoing SMSs
  • perform a USSD request
  • send telephone data to the C&C (telephone number, country, IMEI, model, OS version)
  • send the C&C a list of apps installed on the mobile device
  • send an SMS to a number specified in a command

There are pros and cons of using Tor. On the plus side, it is impossible to shutdown the C&C. One of the main disadvantages, however, is the need for additional code. For Backdoor.AndroidOS.Torec.a to use Tor it will have required a lot more code than that required for its own functionality.

The first Tor Trojan for Android

Your email address will not be published. Required fields are marked *

 

  1. Darren Chaker

    I heard about the release of this Trojan for Android and must say this is a very concise and well written post, with great visuals too. Keep up the good work!

Reports

Ferocious Kitten: 6 years of covert surveillance in Iran

Ferocious Kitten is an APT group that has been targeting Persian-speaking individuals in Iran. Some of the TTPs used by this threat actor are reminiscent of other groups, such as Domestic Kitten and Rampant Kitten. In this report we aim to provide more details on these findings.

Andariel evolves to target South Korea with ransomware

In April 2021, we observed a suspicious Word document with a Korean file name and decoy. It revealed a novel infection scheme and an unfamiliar payload. After a deep analysis, we came to a conclusion: the Andariel group was behind these attacks.

Operation TunnelSnake

A newly discovered rootkit that we dub ‘Moriya’ is used by an unknown actor to deploy passive backdoors on public facing servers, facilitating the creation of a covert C&C communication channel through which they can be silently controlled. The victims are located in Africa, South and South-East Asia.

Subscribe to our weekly e-mails

The hottest research right in your inbox