10.1 What are three broad mechanisms that malware can use to propagate? 10.2 What are four broad categories of payloads that malware may carry? 10.3 What are typical phases of operation of a virus or worm? 10.4 What mechanisms can a virus use to conceal itself? 10.5 What is the difference between machine-executable and macro viruses? 10.6 What means can a worm use to access remote systems to propagate? 10.7 What is a “drive-by-download” and how does it differ from a worm? 10.8 What is a “logic bomb”? 10.9 Differentiate among the following: a backdoor, a bot, a keylogger, spyware, and a rootkit? Can they all be present in the same malware? 10.10 List some of the different levels in a system that a rootkit may use. 10.11 Describe some malware countermeasure elements. 10.12 List three places malware mitigation mechanisms may be located. 10.13 Briefly describe the four generations of antivirus software. 10.14 How does behavior-blocking software work? 10.15 What is a distributed denial-of-service system?