Malware is the codename for malicious software and refers to any software that can access a computer system without the consent of the owner. Software can be classified as malware based on the perceived motive behind its creation rather than its features. Some people consider defective software as malware, but this is a wrong classification. Defective software is originally intended to be helpful but for the harmful bugs in it, while malware is designed to be harmful to computers.

Malware are very common nowadays, especially on the Internet and may come in several forms. Some of them are advertised as useful programs and others come attached to other useful materials on the internet. E-mail messages may also contain malware that gets attached to the user’s computer when the mail is opened for reading. Examples of malware include computer worms, viruses, Trojan horses, spyware, rootkits, dishonest adware and many more.

Microsoft security intelligence reports have shown that, Malware accounts for over 82 percent of online threats in the United Arab Emirates. The details of Microsoft’s Malicious Software Removal Tool reports have revealed that 82.6 percent of all computer threats detected on infected computers are malware. The reports went further to show that the most common malware in the UAE was worms, followed by Trojan horses.


Computer worms are malware that have the ability to replicate by themselves. They send copies to other computers on the network of the infested computer, without the intervention of the user. Worms do not need to attach themselves to any file to spread and may cause harm to the network by consuming a lot of bandwidth. Examples of computer worms include Morris worm, Mydoom, ExploreZip worm and payload. Worms may also encrypt files and send documents via e-mail to allow the creation of a zombie on the computer by installing a backdoor.

Trojan Horses

A Trojan horse may come as a useful program to the user but instead helps unauthorized access to the computer. It is not self-replicating as with the worm. The users themselves usually install them as they look like useful programs. Trojans open the infested computer for access by hackers who access it to perform their activities. Trojans may allow a hacker to perform Denial-of -service attacks, data theft, downloading and uploading of files, deletion of files, keystroke logging and viewing the user’s screen.


Viruses are the well-known form of computer malware. Viruses attach themselves to files on an infested computer and are spread by means of storage devices. Viruses are dangerous to infested computers as they corrupt files and may eventually crash the computer.


Rootkits do not cause any harm to the computer but allow the concealment of malicious programs as well as human attackers on a computer system. They keep the files of malicious software from being read and may also defend malicious software against removal.

Malware should be a major concern of organizations and anybody who owns a computer. No computer is safe from malware so far as it is on network or copies information from other computers, directly of indirectly. It is not enough to have antimalware on a computer, but have drastic measures to prevent the computer from being infected.