How Does a Botnet Work?
A Botnet is a group of connected devices, including computers, tablets, smart TVs and even some IoT (Internet of Things) devices like webcams or soundbars that have been infected with malware and controlled by cybercriminals. Once compromised, these devices are then used to launch attacks on other parties. They work behind the scenes, and users are usually unaware that their devices have been taken over by a botnet. Attackers can use bots to collect keystrokes and form grabbing to steal online credentials and sell them on the black market for DDoS attacks or other services, or they can simply rent out their bots as an attack-for-hire service.
These bots are controlled by a criminal known as a bot herder who directs them to perform various tasks, such as attacking websites or sending spam emails. While earlier botnets were centralized, newer bots operate using a peer-to-peer architecture. This decentralized model makes it more difficult to kill off a botnet by tracking down and closing the command center. In order to remove a bot infection from a device, strategies may include reformatting the system, running a factory reset and reinstalling software from a backup.
Cybercriminals create botnets for a variety of reasons, ranging from activism to profit-based business models. Typically, they aim to exploit website vulnerabilities or crack weak authentication methods to gain remote access to devices. Once that is done, they use self-propagating malware to recruit additional hardware devices into the botnet. Eventually, the attackers have enough devices at their disposal to cause significant amounts of damage and disruption.