This is a family of three viruses - two of which only infect COM files, but
the third also infects EXE files.
This virus is not particularly common, but it contains a different virus:
A boot sector virus, which has spread much further than the file virus.
Kampana infects MBR's on hard disks and DOS boot sectors on floppy
disks. There are several known versions. One of them is unable
to infect floppies at all, and another one activates after 400
boot-up, when it displayes the following message:
VIRUS ANTITELEFONICA (BARCELONA)
After this the virus overwrites a part of the hard disk, destroying
practically all the data on the disk.
Another known variant of Kampana (known to F-Secure anti-virus
products as Kampana (C)) activates after 333 boot-ups, doing a
similar destruction routine, but this version does not display any
texts. This variant does include the text 'Grupo Holocausto' inside
of its code, though.
All known variants of Kampana use stealth-methods to hide themselves
while they are resident in memory, so an infected machine must
be booted from a known clean floppy before check-up and disinfection.
Kampana is only able to spread from machine to another via floppy
disks, and it will only infect the hard disk when the machine
is tried to boot from an infected floppy. Once the hard disk is
infected, practically all floppy disks used in the machine will
get infected.