What is a Botnet?
A botnet is a network of hijacked Internet-connected devices infected with malware that can be remotely controlled. A hacker/cybercriminal known as a bot herder uses these infected systems to carry out various types of cyberattacks such as denial-of-service attacks, online scams, data breaches and more. Candidates for botnet recruitment can include traditional computers like desktops and laptops or IoT devices. Once the devices are infected with remote control tools known as RATs (remote access Trojans), they can be controlled by the attacker from a distant location.
The attacker can then direct the swarm of devices to perform tasks such as downloading and running malicious software, sending spam, and even mining cryptocurrency. They can also collect personal information and execute phishing attacks. For example, one of the most notorious financial breaches used a botnet to steal millions of dollars directly from multiple enterprises over short periods of time.
Once the bot-herder has accumulated a large network of infected systems, they can rent or sell their control to other criminals on the dark web or black market. This allows them to generate significant revenue by performing DDoS attacks, mass email spam campaigns or other malicious activities that target the victim and their connections.
Botnets can be hard to stop, but there are several steps individuals and organizations can take to protect their connected devices. The most effective way to prevent a device from becoming part of a botnet is to install security patches and updates for the operating system on which it runs. Additionally, it is important to avoid clicking on links in emails, text messages or social media posts as they can be the delivery mechanism for bots.