Worm (Generic)

A worm is a program that replicates by using a computer's resources to make copies of itself, then spreading those copies to any other accessible computers or devices on a connected network.

Installation

Worms are often spread disguised as a tantalizing video or image file, or as a legitimate program. This is a common social engineering tactic to trick users into running the file and unwittingly infecting their own device or account.

Worms have been found spreading on almost every kind of network. The most common way they spread is over the Internet or via emails, but mobile networks have also seen their fair share of worms. Social media networks such as Facebook or Twitter and instant messaging (IM) channels have also been used to distribute worm copies. In these cases, the worm is usually designed to take control of an account on the social network, rather than a device.

Usually, worms will focus on spreading over one network ' for example, just over the Internet or over a specific social media network. Some more advanced worms will try and spread over multiple networks for maximum impact.

Impact

A device that has been infected by a worm may have its performance reduced, as the worm is using the machine's resources to copy itself. A network that has multiple infected devices on it may also suffer performance issues, as its bandwidth and resources are taken up by worm copies being distributed to connected devices.

Worms may be used offensively by attackers to perform other harmful activities, such as launching Denial of Service (DoS) attacks. They may also be used to deliver other threats, such as trojans.