The Trojan known as Tinba or Tiny Banker has been spotted in attacks aimed at online banking users in Russia, which is noteworthy because the country is not often targeted in such campaigns.
Abuse.ch, a Swiss security site that tracks malware campaigns, reported seeing nearly 33,000 Tinba 2.0 infections last month, more than a third of which were located in Russia and nearly a quarter in Poland.
According to Dell SecureWorks, Tinba’s configuration files reveal that the threat is designed to target a major Russian bank, which is among the biggest in Europe, and two of the country’s payment service providers.
Many of the cybercrime schemes involving the top banking Trojans are run by groups from Russia and Ukraine. However, these groups focus their activities on Internet users in North America and Europe and tend to avoid targeting banks in their own countries to avoid heat from law enforcement.
While several Russian and Ukrainian nationals have been prosecuted in the United States for cyber crimes, black hat hackers from these countries don’t seem to be discouraged. However, they do avoid local financial organizations, especially since Ukrainian and Russian authorities teamed up in 2013 to target a group responsible for stealing $250 million from Ukrainian and Russian banks using the Trojan known as Carberp.
In addition to Russian banks, Tinba has also been increasingly used to target the customers of Asian financial organizations, particularly ones in Japan.
“Currently, Tinba threat actors are focused on customers of Shinkin financial institutions. Shinkin banks are cooperative regional financial institutions that service small and medium businesses, as well as local residents,” Dell SecureWorks reported on Tuesday.
There are two main versions of the threat: Tinba 1.0, whose source code was leaked in July 2014, and Tinba 2.0, which brings several significant improvements compared to its predecessor. Both versions are believed to be controlled by threat groups operating from Eastern Europe.
Tinba 2.0 has been sold as a botnet kit to multiple groups. Dell SecureWorks believes there are over a dozen actors operating Tinba 2.0 botnets.
“The malware provides an effective and lightweight alternative to the Zeus banking trojan, with numerous methods to harvest sensitive information from a compromised system,” noted Dr. Brett Stone-Gross, senior security researcher with Dell SecureWorks. “Threat actors can use this information to steal a victim’s identity and commit ACH or wire fraud. The command-and-control communications rely on a domain generation algorithm (DGA) and verify the legitimacy of the server through RSA cryptography, making Tinba 2.0 botnets more challenging to disrupt. As a result, CTU researchers expect Tinba 2.0 to continue to remain popular in the foreseeable future.”