A botnet is a group of internet-connected devices that are controlled by a single individual or group, often without the knowledge or consent of the device owners. These devices can be used to launch a variety of malicious attacks, such as distributed denial-of-service (DDoS) attacks, spam campaigns, and data theft. Botnet malware is the software that is used to infect devices and turn them into part of a botnet.

Gafgyt, also known as BASHLITE, is a botnet affecting Internet of Things (IoT) devices and Linux-based systems. The malware aims to compromise and gain control of these devices, often by exploiting weak or default passwords, as well as known vulnerabilities. Gafgyt has been around since 2014 and has evolved into multiple variants, each with its own set of features and capabilities, including the ability to launch distributed denial of service (DDoS) attacks.

Mirai is a self-propagating malware that scans the internet for vulnerable IoT devices and infects them to create a botnet. Mirai variants utilize lists of common default credentials to gain access to devices. Mirai's primary use is for launching distributed denial-of-service (DDoS) attacks, but it has also been used for cryptocurrency mining.