An initial infection is still carried out via e-mail, which touts a link that when clicked downloads a number of malware components to a victimized machine. Once on a PC, however, the malicious code injects itself into the network stack as a rootkit and analyzes all outbound Web traffic

"It has hooks for boards, e-mail, and blogs," said Alperovitch. When a user on an infected PC posts a message to a forum or blog, or sends a message via popular Web-based mail services such as Hotmail, Gmail, and Yahoo Mail the Trojan adds text to the entry or message.

resulting in new links to more malware...