Hacktivist

Malicious users intent on waging an attack against a person or system. Crackers may be motivated by greed, power, or recognition. Their actions can result in stolen property (data, ideas, and so on), disabled systems, compromised security, negative public opinion, loss of market share, reduced profitability, and lost productivity. The correct name for an individual who hacks into a networked computer system with malicious intentions. The term “hacker” is used interchangeably (although incorrectly) because of media hype of the word “hacker. ” A cracker explores and detects weak points in the security of a computer networked system and then exploits these weaknesses using specialized tools and techniques.
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Also referred to as defacement or Web site defacement, a form of malicious hacking in which a Web site is vandalized. Often, the malicious hacker will replace the site’s normal content with a specific political or social message, or will erase the content from the site entirely, relying on known security vulnerabilities for access to the site’s content.
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An information security "exposure" is a system configuration issue or a mistake in software that allows access to information or capabilities that can be used by a hacker as a steppingstone into a system or network. The condition of being exposed to asset loss because of a threat. Exposure involves being susceptible to the exploitation of a vulnerability by a threat agent or event. The potential loss to an area due to the occurrence of an adverse event.
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A person who attempts to break into computers that he or she is not authorized to use. Historically, a technology enthusiast who does not have malicious intent. Many authors and the media often use the term when they are actually discussing issues relating to crackers or criminal hackers. Unauthorized user who attempts to or gains access to an information system.
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The hacker who is in control of a botnet. Also called bot herder.
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