Banker Trojans have proven to be a reliable and effective tool for attackers. Allowing them to  quietly steal large amounts of money from unwitting victims.

Zeus, Carberp and many other Torjans have made piles of money for their creators and the attackers who use them, and researchers have been looking at a newer banker Trojan that has the ability to bypass the SSL protection for banking sessions by redirecting traffic through the attackers’ own domains.

The Trojan, which is being called either Dyre or Dyreza by researchers, uses a technique known as browser hooking to intercept traffic flowing between the victim’s machine and the target Web site. The malware arrives in users’ inboxes through spam messages, many of which will look like messages from a financial institution.

The list of targeted banks includes Bank of America, Natwest, Citibank, RBS and Ulsterbank. Researchers say that much of the activity from the Trojan so far is in the U.K.

When a victim opens the attached zip file in a spam message, the malware installs itself on the machine and then contacts a command-and-control server. Researchers at CSIS in Denmark located a couple of the C2 servers and discovered that one of them had an integrated money mule panel for several accounts in Latvia. The goal of the malware, of course, if to steal users’ credentials for online banking and other financial sites. Various banker Trojans go about this in different ways, and Dyreza’s creators decided to employ browser hooking to help defeat SSL.

When users go to one of the targeted financial sites and attempt to log in, the data is intercepted by the malware and sent directly to the attackers. Victims would not have any visual cues that their data is being siphoned off or that the malware is redirecting their traffic to a domain controlled by the attackers and it’s no longer encrypted.

The Dyreza malware has the ability to hook Google Chrome, Mozilla Firefox and Internet Explorer.

Until further notice be very careful when dealing with emails from bank accounts as not many these days will email you in this manner!