Summary

This virus contains a couple of text strings:

'MusicBug v1.06 MacroSoft Corp.' and '-- Made in Taiwan --'

Like the Azusa virus, this virus infected the computers of a Taiwanese producer of VGA-driver software, which then distributed infected, shrink wrapped, write-protected diskettes to unsuspecting users.

Additional Details

When a computer has been infected for four months, the virus enables the "music" effect. Then it uses the system timer as a random generator to determine whether it should play a tune or not. The chance of that to happening is close to 14 percent. The tune it plays is a sequence of 36 notes, each of which is selected at random from a list of eight basic notes. The authors idea was probably to increase the virus' chances of spreading, by making it stay silent for the first four months after it infects a system.

Music Bug infects the DOS Boot sector and also recognises 360K and 1.2MB 5.25" diskettes. It will not attempt to infect 3.5" diskettes. It assumes the diskettes always have 12-bit FAT entries and hard disks use 16-bit FATs, so it might be quite destructive when this is not the case.