A zombie computer is a computer which has been compromised, with control given over to a remote third party. Zombie computers are usually infiltrated through a malware of some kind, which provides access to the third party who usually uses their control for malicious purposes. Despite this, the computer owner is often unaware that their machine has been compromised.
Many zombie computers controlled by the same actor are usually used as part of a botnet (also known as a zombie army), which are often used as part of a DDoS attack, or to send spam.
Last updated: 3 September 2017