The Russian security firm that originally acknowledged the Flashback botnet spread across 650,000 Macs continues to analyze the behavior of the Trojan, as “Files downloaded by the Trojan horse from servers controlled by criminals have become one of the main subjects for analysis.”

“Doctor Web virus analysts continue to study the first-ever large-scale botnet created by means of BackDoor.Flashback and comprised of computers running Mac OS X,” says the firm.