Information Assurance

10.1. Introduction

With 20 years of research on vulnerability analysis and intrusion detection, most critical computer networks are now under the protection of various security measures, such as access control, firewalls, intrusion detection systems (IDSs), and vulnerability scanners. With proper implementations, such measures can effectively thwart intrusion attempts made by amateur attackers and so-called script kiddies. However, real nightmares to a security administrator are usually caused by more experienced attackers who can easily circumvent basic security controls and detections through multistep intrusions. In such an intrusion, an attacker launches multiple attack steps that prepare for each other such that privileges can be gradually ...