The Bravo virus was found from South Africa in December 1993. It is a stealth virus which infects floppy boot records and hard disk master boot records. When the virus is Resident, in memory, the changes made to the hard disk cannot be seen.
Bravo stays resident in the interrupt vector table in low system memory. For this reason, there is no decrease in available system memory. The virus may crash the PC occasionally, especially with local area networks.
The virus will only infect hard drives when an attempt to boot from an infected diskette is made. Once the virus has infected the hard drive, all non-protected floppies used in the machine will be infected.
Bravo virus is one sector long, and it stores the original boot sector to last sector of the root directory. The name of the virus comes from a text string 'Bravo', which the virus contains. The virus might also sometimes overwrite the boot sector of floppies with this string.
Disinfection & Removal
Description Created: Mikko Hypponen, F-Secure