Part 7 explores four topics that play important roles in computer security. They underlie the security of modern systems and networks.

Chapter 22, “Malicious Logic,” discusses programs set up by attackers to perform actions that violate the site's security policy. The programs act with the privileges of an authorized user but execute without that user's knowledge.

Chapter 23, “Vulnerability Analysis,” describes penetration testing. Although important as a standard a posteriori testing technique, penetration testing models the way attackers analyze a system when determining how best to attack it. The insight gained from this mode of thinking is invaluable to defenders. Chapter 23 also discusses models of vulnerabilities to gain insight into why they occur.

Chapter 24, “Auditing,” considers auditing and logging. These operations are important in the analysis of attacks. However, they introduce complexities, particularly in the areas of knowing what to log and how to correlate logs kept on different systems.

Chapter 25, “Intrusion Detection,” examines the different ways to detect and respond to various types of intrusions. Intrusion detection automates analysis of logs and systems to detect attacks and, in some cases, counter them.