What Malicious Code?

Malicious code refers to a broad category of software threats to our network and systems. Perhaps the most sophisticated types of threats to computer systems are presented by malicious codes that exploit vulnerabilities in computer systems. Any code which modifies or destroys data, steals data , allows unauthorized access, exploits or damage a system, and does something that user did not intend to do, is called malicious code. There are various types of malicious code we will encounter, including Viruses, Trojan horses, Logic bombs, and Worms.

A computer program is a sequence of symbols that are caused to achieve a desired functionality; the program is termed malicious when their sequences of instructions are used to intentionally cause adverse affects to the system. In the other words we can’t call any “bug” as a Malicious Code. Malicious codes are also called programmed threats. The following figure provides an overall taxonomy of Malicious Code.