Heard of Friday ghosts? The 'Nyxem-D' and 'Nyxem-E' email worms that come with a timer to strike every month on a precise day, work the same way.
These worms spread via pornographic messages like 'Kama Sutra pics,' and they are variants of the 'Worm.Win32.VB.bi,' first reported by MicroWorld, the global anti-virus and content security specialists. Examining the code, MicroWorld found that Nyxem works with a timer and is expected to strike on the 3rd of every month.
On the February 3, Nyxem is programmed to overwrite all infected files. It shrinks files to 20 bytes and displays an error message when you try to open them. Although this worm is not very sophisticated, it is spreading really fast. On a network, this worm can start spreading from an unprotected PC and can destroy important files, said a MicroWorld media release.
Nyxem proliferates by exploiting human tendency to be lured by sexual content. Some of the title lines of the mails are 'The best video clip ever,' 'school girl fantasies gone bad,' 'a great video,' etc, 'Kama Sutra pics,' 'Arab sex DSC-00465.jpg', et cetera.
One of the oldest forms of virus proliferation, this method is not new but is still effective as the virus had already infected more than half a million PCs around the world till Monday morning, claimed MicroWorld.
In nature, Nyxem is a mass mailing worm that disables security software on the computer and harvests email addresses from infected PCs. It comes with an emailing engine and installs itself in the registry.
Resolution
Timely updates of escan and mailscan software will enable you to keep off threats of this nature. In case of infections, you can download free virus and spyware scanning toolkit 'MWAV' from http://mwti.net/virus_info/virusalertd.asp?vid=798 or other anti-virus software developers.