Describe malware as malicious code or malicious software. Point out that other attacks that use software, such as redirect attacks and denial-of-service attacks, also fall under this threat. Note that the malicious code attack includes the execution of viruses, worms, Trojan horses, and active Web scripts with the intent to destroy or steal information.
Explain that the polymorphic, or multi vector, worm is a state-of-the-art attack system. Point out that these attack programs use up to six known attack vectors to exploit a variety of vulnerabilities in commonly found information system devices.
Emphasize to students that when an attack makes use of malware that is not yet known by the antimalware software companies, it is said to be a zero-day attack.
Summarize other forms of malware, including covert software applications—bots, spyware, and adware—that are designed to work out of sight of users, or via an apparently innocuous user action. Use Table 2-7 to review some of the most dangerous malware attacks to date.