The infection, known as “Bagle” or “Beagle,” appears to be the handiwork of spammers keen to collect a batch of e-mail addresses they can then re-sell to other spam e-mail marketers or keep for their own use.
“Bagle” also contains code that could turn an infected computer into a veritable “spamming” machine.
Security experts said it is patterned after the recent “Sobig” and “Mimail” outbreaks, which also turned scores of computers into zombie machines that spammers can control remotely to send torrents of get-rich-quick and sex aid messages to other computer users.
“It seems perfectly possible that Bagle is yet another worm written by spammers. When they have enough infected computers, they could automatically install invisible e-mail proxy servers on each machine and start spamming through them,” said Mikko Hypponen, research manager at Finnish anti-virus firm F-Secure.
A host of virus-detection firms had placed their most severe ratings on the e-mail, noting it was spreading quickly from Asia through Europe and now to the United States.
The e-mail infection, or worm, contains a familiar subject line of “Hi” and an executable file attachment identified by “.exe.” The body of the e-mail contains random characters.
The virus is triggered once a computer user clicks on the attachment, setting in motion an aggressive e-mail harvesting program that scans all documents on the infected computer and throughout the network it is attached to.
Computer analysts said most corporate e-mail filters should be able to block the infected e-mail, but that home users were particularly vulnerable.