Sobig.F Slams the Enterprise
- By Scott Bekker
Sobig enjoyed a resurgence as messages generated by a new variant of the mass-mailing worm flooded e-mail servers and user Inboxes on Tuesday.
Most anti-virus vendors referred to the worm as Sobig.F. Symantec upgraded the worm to a category 3 on its threat scale on Tuesday, due to the number of reports.
Using its own internal SMTP engine to send out messages with mostly spoofed From addresses, the worm greeted users with subject lines including, "Re: That movie," "Re: Wicked screensaver," Re: Your application," Re: Approved," "Re: Re: My details," and "Re: Details."
A brief message reading "See the attached file for details" or "Please see the attached file for details," introduced one of many possible attachments, all with file names ending in .pif or .scr.
Once a user clicks on the attachment, the worm begins searching for e-mail addresses and network shares to spread itself to and in some cases can download trojans or other files to begin stealing information from systems.
According to anti-virus researchers, the worm deactivates on Sept. 10, 2003.
Sobig.F is a variant on a spoofing, mass-mailing worm, also known as PalyH, that began spreading in May and purported to come from email@example.com. That worm prompted Microsoft to alert users that it never sends patches via e-mail.
Scott Bekker is editor in chief of Redmond Channel Partner magazine.