Also known as:
Ashar, (C)Brain, Clone, Nipper, Pakistani, PakistaniBrain
Memory resident stealth boot sector infector
The Brain virus is a memory resident stealth boot sector infector that changes the infected disk's volume label to "(c) brain" or "(c) ashar" depending on variant.
While no longer in-the-wild, Brain achieved notoriety for being the first known PC virus. It infected boot sectors, hooking into INT13. If the virus were resident in memory, the boot sector would look normal.