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Zombies and Botnets

NCJ Number
Kim-Kwang Raymond Choo
Date Published
March 2007
6 pages
This paper examines the activities and consequences associated with "botnets" (programs that allow attackers to remotely control vulnerable computers and form virtual networks of computers to do their bidding) and provides examples of recent "botnet" incidents in Australia so that Internet users can be better informed of types of risks.
Bot programs are codes or programs that operate automatically as agents for a user or another program. They are forwarded to victims by various means, such as e-mail attachments, peer-to-peer networks, and visits to an infected Web site. Bot programs typically exploit system vulnerabilities and software insecurities or use hacker-installed "backdoors" that allow malicious codes to be installed on computers without the computer owners' consent or knowledge. They then load themselves into such computers, often for harmful purposes. The infected computers are turned into "zombies." Electronic payment systems and online auction sites have been targeted by bot programs for illicit financial gain. Also, "zombie" networks are used to disseminate massive amounts of spam advertisements for potential financial gain. "Zombie" networks have also been used for e-mail contacts that direct recipients to a fake Web site where they are instructed to provide personal information that can be used to make withdrawals from a victim's bank account. Many of the wide-ranging activities and consequences that result from botnet attacks are offenses under Australian law. This paper cites the provisions of Australia's Criminal Code Act 1995 that pertain to bot-program attacks. Five cases of recent botnet incidents are described. 25 references