NEW YORK (AP) As awareness about Internet security rises, virus writers are finding creative ways to trick computer users into opening harmful e-mail attachments.
To keep Internet users off guard, the latest virus changes the e-mail's subject line to reflect recent files on the sender's computer. So friends and co-workers may receive such messages as ''Birthday party plans for Bob'' or ''Information about Motorola.''
''The e-mail goes to people who know you're working on that project,'' said Mikko Hypponen, manager of anti-virus research at F-Secure Corp. in Helsinki, Finland. ''It's really convincing.''
Plus, said David Remnitz of security firm IFsec in New York, the mutations deny recipients and computer administrators ''a common ground to judge whether a message is actually a virus.''
The ''Love Bug'' virus spread quickly two weeks ago by seducing recipients with a love letter purportedly from a friend.
Within days, variants disguised themselves as an e-mail joke or a receipt for a Mother's Day gift. Some viruses even pretended to come as warnings from Symantec Corp., a maker of anti-virus software.
''Someone thought that by falsifying credibility, maybe that will get them into the system,'' said Patrick Martin, a Symantec product manager. ''Instead of forcing a virus down your throat, they try to entice you to do to it yourself.''
Virus writers have tempted computer users previously with a South Park cartoon character and tools to fix the Year 2000 glitch.
Clever social engineering helps viruses spread far, said David Perry, director of public education with anti-virus vendor Trend Micro. Less-clever viruses his company discovers hundreds each month die out uneventfully.
''Virus writers are trying a lot of stuff by trial and error,'' Perry said. ''That's the nature of software development and the nature of human endeavor. Novelty works.''
As a result, security becomes a game of cat-and-mouse. Anti-virus vendors try to stay a step ahead of virus writers, who try to stay a step ahead of public awareness.
Americans are generally savvy about viruses, claimed Susannah Fox, director of research at the Pew Internet and American Life Project. But, she fretted: ''As computer virus writers get trickier, are Americans keeping up with them?''