Common name | Form |
---|---|
Technical name | Form |
Aliases | Form18, Forms |
Family | N/A |
Classification | Virus |
Type | DOS |
Subtype | Boot sector virus |
Isolation | June 1990 |
Point of isolation | Switzerland |
Point of origin | Switzerland (?) |
Author(s) | Unknown |
Form was a boot sector virus isolated in Switzerland in the summer of 1990 which became very common worldwide. The origin of Form is widely listed as Switzerland, but this may be an assumption based on its isolation locale. The only notable characteristics of Form are that it infects the boot sector instead of the Master Boot Record (MBR) and the clicking noises associated with some infections. Infections under Form can result in severe data damage if operating system characteristics are not identical to those Form assumes.
It is notable for arguably being the most common virus in the world for a period during the early 1990s.
Form infects the boot sector. When a computer is booted from an infected sector, Form goes resident, hooks the interrupt vector table, and runs the original boot sector which it has hidden in an area it flags as defective. It will subsequently infect any media inserted into the machine.
Form has a range of symptoms, most of which will not be evident in all infections:
Form was listed as spreading by the WildList from the first ever version of the WildList in July 1993 until January 2006. [1]
As with most boot viruses, a Form infection is a rare find in modern times. Since the advent of Windows, boot viruses have become increasingly uncommon, including Form. Generally, Form infections are due to the use of floppy disks infected during the original pandemic that have since been taken out of storage.
Form has a number of variants. The widely documented versions are as follows.
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