The statistics produced by the online scanner in May 2008 are nothing short of revolutionary. Virtumonde.gen, which has been the unquestionable leader throughout 2008, has completely disappeared from view. Worms from the Bagle family, together with several variants of Trojan.Win32.Dialer, have also dropped out of the Top Twenty.
They have been replaced by a new generation of malicious programs - file viruses, which are, unfortunately, much more dangerous.
These new entries came in at 3 and 4 (variants of the Allaple worm), 2 and 10 (variants of Virut), 12 (Xorer) and 20 (Alman.b). Never before have file viruses enjoyed such success, with six entries and three different families in our Top Twenty rankings.
Of this group, the Virut viruses pose the most serious threat. In April, we mentioned that these programs are bots used to build zombie networks. Infected computers can be used to conduct DDoS attacks, send spam and distribute new malicious programs.
In comparison, even the ranking's veterans, the Brontok.q and Rays worms, seem relatively innocuous. Brontok has surrendered top place to the Trojan-Downloader program Pendix.d. We first detected this Trojan back in December 2007, but it is only now that its spread has reached epidemic levels.
Both variants of the Chinese backdoor program Hupigon, and programs from the Trojan Spy OnlineGames family (which are designed to steal online game accounts), also disappeared from the rankings after several months of activity.