What is Computer Worm
Definition: A computer worm is a malicious, self-replicating software program (popularly termed as 'malware') which affects the functions of software and hardware programs.
Description: It fits the description of a computer virus in many ways. For example, it can also self-replicate itself and spread across networks. That is why worms are often referred to as viruses also. But computer worms are different from computer viruses in certain aspects. First, unlike viruses which need to cling on to files (host files) before they can diffuse themselves inside a computer, worms exist as separate entities or standalone software. They do not need host files or programs. Secondly, unlike viruses, worms do not alter files but reside in active memory and duplicate themselves. Worms use parts of the operating system that are automatic and usually invisible to the user. Their existence in the system becomes apparent only when their uncontrolled replication consumes system resources, slowing or halting other tasks in the process. In order to spread, worms either exploit the vulnerability of the target system or use some kind of social engineering method to trick users into executing them. Once they enter a system, they take advantage of file-transport or information-transport features in the system that allows them to travel unaided. A computer worm called 'Stuxnet worm¡¯ turned heads the world over recently when it attacked the nuclear facilities of Iran. This worm reportedly destroyed roughly a fifth of Iran's nuclear centrifuges by causing them to spin out of control by increasing the pressure on the spinning centrifuges, while displaying that everything was under control. It managed this feat by replaying the plant's protection system values in the control room while the attack was happening.
Description: It fits the description of a computer virus in many ways. For example, it can also self-replicate itself and spread across networks. That is why worms are often referred to as viruses also. But computer worms are different from computer viruses in certain aspects. First, unlike viruses which need to cling on to files (host files) before they can diffuse themselves inside a computer, worms exist as separate entities or standalone software. They do not need host files or programs. Secondly, unlike viruses, worms do not alter files but reside in active memory and duplicate themselves. Worms use parts of the operating system that are automatic and usually invisible to the user. Their existence in the system becomes apparent only when their uncontrolled replication consumes system resources, slowing or halting other tasks in the process. In order to spread, worms either exploit the vulnerability of the target system or use some kind of social engineering method to trick users into executing them. Once they enter a system, they take advantage of file-transport or information-transport features in the system that allows them to travel unaided. A computer worm called 'Stuxnet worm¡¯ turned heads the world over recently when it attacked the nuclear facilities of Iran. This worm reportedly destroyed roughly a fifth of Iran's nuclear centrifuges by causing them to spin out of control by increasing the pressure on the spinning centrifuges, while displaying that everything was under control. It managed this feat by replaying the plant's protection system values in the control room while the attack was happening.