ABSTRACT
CONTENTS 2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.2 Overview of Cyber Intrusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.2.1 Malware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 2.2.2 Vulnerabilities Exploitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2.2.3 Denial-of-Service Attack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2.2.4 Web-Based Attacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2.2.5 DNS Attack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 2.2.6 Organized Attacks and Botnets . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.2.7 Spam and Phishing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.2.8 Mobile Device Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.2.9 Cyber Crime and Cyber Warfare . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.3 A Taxonomy of Cyber Intrusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.1 Introduction Since the first computer virus Creeper appeared in 1971, cyber attacks have been growing explosively and became a serious problem these days. Throughout the 1990s, the rise of commercial interest on the Internet has propelled information infrastructure as the core component of a global economy. Government agencies and businesses have become increasingly dependent on information technology for daily operations to increase their productivity. However, the increasing number of cyber threats and attacks has become a serious issue for the entire economy and government systems. Millions of attacks have been reported and hundreds of millions of nodes are
cyber attackers not only theft and information harvesting, but use the compromised computers for criminal purposes, such as launching distributed denial-of-service (DDoS) attacks on some businesses or agencies. Cyber wars, as defined by Richard A. Clarke “...actions by a nation-state to penetrate another nation’s computers or networks for the purposes of causing damage or disruption” [47], have become frequent and caused significant damage in recent years.
