Melissa's back. And this time, she's adding Macs to her diet.
Virus detection resources have reported a variant of the Microsoft Word Macro virus that ravaged computer systems two years ago, with the new Melissa strain turning up in Office 2001 for Mac Word documents. That means the virus, which didn't affect Mac users when it first struck in March 1999, could appear on Macs this time around.
Still, Mac users shouldn't panic, experts caution. MessageLabs.com, an application service provider, characterizes the virus as a "minor outbreak of Melissa.W". And virus protection software makers are already on the case.
Vincent Gullotto, senior direct of McAfee's Avert Labs, says Virex users with version 6.1 of the Network Associates product face no threat from the software. Likewise, the current version of Symantec's Norton AntiVirus product will detect the virus; an update available within 24 hours should fix Macs affected by the Melissa strain. NAV users can get the update by using the software's LiveUpdate feature, says David Loomstein, group product manager for Symantec's consumer products division.
"It's just something to keep a lookout for, and being prepared is always a good idea," Loomstein says.
Like the original Melissa virus, this version arrives via e-mail with the subject line "Important Message From (User Name)." The e-mail contains a file enclosure, usually called Anniv.Doc or something similar. If you get such an e-mail, delete it immediately without opening the attached file, experts say.
When Melissa struck two years ago, it spread when the virus launched Microsoft Outlook and sent the infected attachment to 50 people in a user's Outlook address book. The extra traffic caused by the virus forced e-mail systems and servers to shut down entirely.
That doesn't appear to be happening with Mac users. Loomstein says there are no reports of the Melissa.W virus launching Entourage or any other client for e-mail-borne attacks.
An update on the latest strain of Melissa at Network Associates' McAfee.com Web site warns that although the file format is specific to Office 2001, it can infect host systems running Office 98, as well.
Gullotto believes the Melissa variant was created when a user took an infected document and brought it into Office 2001. The result: the virus was "up-converted," allowing it to infect Mac systems, as well as PCs not immune to the latest Melissa strain.
Mac users escaped unscathed when the Melissa virus first hit in 1999. More than 300 companies reported infections and at least 100,000 PCs were affected in the first week that the virus emerged, according to the Computer Emergency Response Team at Carnegie Mellon University in Pittsburgh.