Backdoor.
A hardware or software-based hidden entrance to a computer system that can be used to bypass the system’s security policies.
BIOS.
An acronym that stands for Basic Input/Output System. The BIOS is a built-in chip in the computer which contains a set of instructions that tells the computer how to act.
Buffer-overrun.
A condition that results from adding more information to a buffer than it was designed to hold. An attacker may exploit this vulnerability to take over a system.