Malicious Mobile Code

Chapter 1. Introduction

Chapter 1 is an introduction to the world of malicious code and its authors. You will learn there is a lot more to the rogue program world than computer viruses and worms. The chapter discusses what malicious mobile code is and its classifications. It summarizes the very active virus-writing subculture and the laws written to protect us.

The Hunt

I had been called to a company because it appeared that one of their Windows 98 computers had been hacked. The computer was connected to the Internet and was used for web surfing and email. The only symptom they reported was a significant slowdown in processing. Sure enough, even though the PC had more than enough processor power to run its applications, it was running very sluggishly. The day before it had been a fast and responsive machine. Now, it seemed to struggle with every mouse click and screen change. The mouse cursor hesitantly flashed during operations -- an indication of slow processing. They had already run an antivirus scanner with an updated signature database file. It had found nothing. Still, everyone was suspicious. Malicious mobile code is coming out so fast these days than even the most accurate scanners can’t track all of the new ones.

The first thing I did when I arrived was to disconnect the PC from the Internet by unplugging its network card cable. That way if the machine was being attacked or monitored from the Internet, no more damage could be done. I then hit Ctrl-Alt-Del to see what program ...