Maintaining the security of point-of-sale (POS) systems is a growing concern. A number of malware families targeting them were discovered this year, including Dexter, vSkimmer, BlackPOS and Alina. These are all examples of advanced malware designed to steal payment card information at the point of sale. One of the most interesting commonalities across these malware families is their use of a command-and-control (C&C) communication channel for data exfiltration.
Infections by Dexter
Dexter, for example, is a malware that targets POS systems, first discovered in December 2012 by Seculert. Dexter steals payment card data from the POS system and sends it to a C&C server hosted in the Republic of Seychelles. Most POS systems infected by Dexter run on Windows platforms: More than 50 percent of the infected systems run Windows XP, 17 percent run Windows Home Server, 9 percent run Windows Server 2003 and 7 percent run Windows 7.
Dexter’s method for infecting POS systems has yet to be determined. It is possible that POS systems are infected via drive-by downloads, but there is no evidence that this is the case. Some security experts believe that hackers establish a remote connection to the POS system (using misconfigured firewalls and default passwords on system processes) and then drop malware like Dexter directly on the machine.