ZeuS is a well-known banking Trojan horse program, also known as
crimeware. This trojan steals data from infected computers via web browsers and protected storage. Once infected, the computer sends the stolen data to a bot
command and control (C&C) server, where the data is stored.
The US FBI, Secret Service, and various NY agencies have issued a joint Cyber-Security Advisory warning of the threat posed by the Zeus botnet specifically and wire fraud risks from keylogger trojans in general. Zeus combines
keylogger capabilities with man-in-the-middle (or man-in-the-brower) style attacks to steal online banking credentials.