Malware: Fighting Malicious Code

Infection Mechanisms and Targets

A virus is a piece of bad news wrapped up in protein.

—Sir Peter Medawar, Nobel Prize-winning biologist [12]

Actually, a computer virus is a piece of bad news wrapped up in software.

—Modern retake on Medawar's observation

A virus needs to attach itself to a host program to function. The potential target for infection is any file that can contain executable instructions, such as a standard executable, a disk's boot sector, or a document that supports macros. Let's examine how the infection takes place for some of the most common virus targets.

Infecting Executable Files

Standard executables are a frequent target of computer viruses. After all, these are the programs that are directly launched by the victim as ...