Recently our e-crime unit has detected a new banking trojan, named as
Tatanga, with Man in the Browser (MitB) functions affecting banks in Spain, United Kingdom, Germany and Portugal. Like
SpyEye, it can perform automatic transactions, retrieving the mules from a server and spoofing the real balance and banking operations of the users. Its
detection rate is very low, and the few antivirus engines that can detect it yield a generic result.
The trojan in question is rather sophisticated. It is written in C++ and uses rootkit techniques to conceal its presence, though on occasion, its files are visible. The trojan downloads a number of encrypted modules (DLLs), which are decrypted in memory when injected to the browser or other processes to avoid detection by antivirus software. The modules are the following:
- ModEmailGrabber: It gathers e-mail addresses.
Coredb: It manages the trojan's configuration. The corresponding file is encrypted with the algorithm 3DES.
Comm Support Library: This module implements the encryption of the communication between the trojan and the control panel.
File Patcher: The function of this module is not clear yet. It is suspected that it is in charge of the propagation across folders containing multimedia, zipped or executable files.