malicious hardware - Computer Definition
(1) A virus or other malicious software that is attached to a program preloaded on a computer or external hard drive.
(2) A CPU chip in a computer or handheld device that has a built-in back door, enabling an attacker to gain illegal entrance. Far more difficult than a software virus, it requires access to an assembly line or semiconductor fab in order to replace good parts with infected ones. See trapdoor.