zombie computer
n. A computer containing a hidden software program that enables the machine to be controlled remotely, usually to perform an attack on another computer.

Example Citation:
The new version of a software package dubbed 'Trinoo' allows attackers to infiltrate ordinary desktop computers running Microsoft's Windows operating system. These computers — particularly those connected to high-speed Internet services — could then be used in assaults on other Web sites, security analysts say. ... These tools allow an attacker to place agents on "zombie" computers around the world and then wake them up simultaneously to launch a crippling stream of Web traffic at a target site.
—"New software simplifies denial-of-service attacks," St. Petersburg Times, February 24, 2000

Earliest Citation:
A new form of Denial of Service (DoS) attack caused by the trin00 and Tribe Network Flood programs has been wreaking havoc on bandwidth on a larger scale than ever before, according to Chris Klous, founder and chief technology officer of Internet Security Systems (ISS).

This DoS attack employs a simple concept: sending bogus packets from a remote location to IP routers where they collect and eventually plug up a pipe. The danger is manifested in this version because the hackers are gaining control of as many as thousands of vulnerable zombie computers in order to magnify and direct their full-scale assault against a single victim from all directions.
—Brian Fonseca, "Denial-of-service attacks employ zombie PCs to hit networks," InfoWorld Daily News, December 9, 1999

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