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.

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.