updated 02:45 pm EDT, Fri April 13, 2007
Storm Trojan E-mail Hits
Windows users are being hit by a surge of virus-infected spam e-mail, according to Internet security experts. A variant of a bug nicknamed the "Storm worm" has been appearing in several different versions on a wide scale since Thursday and only threatens to get larger in the near term -- over 5 million messages had been caught as of Thursday alone, the security firm Postini reported. The situation was extreme enough that the firm could see as many as 60 million messages today, making it the largest attack in a year and the single largest contributor to junk e-mail this week.
"We're seeing 50 to 60 times the normal volume of spam," said company senior manager Adam Swidler.
The disturbing success of the worm is in large part due to the combination of the way it tricks users and then infects their machines, the experts noted: while the e-mail can only infect a Windows system by the user running a password-protected ZIP file, the message scares readers into believing the PC has been infected and that the attached worm is the cure. "They're telling people that their e-mail access is about to be cut off, and that they have to install this patch to continue using [e-mail]," Swidler explained.
The hack then expands aggressively, installing a rootkit for remotely hijacking the PC; the code also automatically scans for e-mail addresses on the user's system to forward the e-mail, guaranteeing that the worm spreads to many more computers than the infected host. It can also randomize itself and auto-update through a unique peer-to-peer system to help avoid anti-virus tools.
Security analysts have so far suggested that user education on unexpected attachments is the best defense, but note that Symantec and other companies will have updatead means of finding the Storm worm today.