What is a Botnet?
A Botnet is a network of hijacked computers, devices, and other connected things infected with malware that are mindlessly controlled by cybercriminals to carry out a variety of nefarious activities like cryptocurrency mining, spamming, distributed denial-of-service attacks (DDoS), phishing, form grabbing, and selling credentials online. Botnets are notoriously difficult to detect by traditional malware signatures due to their ability to mutate and evade detection.
The hacker that controls a botnet, known as the bot master or bot herder, has several ways to gain access to and control the infected machines. These methods are known as command-and-control (C&C).
Traditional botnets used a client-server model where a server on a domain, website, or Internet Relay Chat network controlled by the bot herder was contacted by the bot software on infected devices to both receive commands and transmit data back to the C&C server. However, since law enforcement and security agencies have been cracking down on centralized servers, most bot herders are now using a P2P system in which each infected device functions as both client and server, connecting with other devices to share communications and malware updates.
A botmaster can infect a wide range of devices, from desktop computers to smartphones, tablets, and IoT devices. They then use the bots to perform nefarious activities, including cryptomining, stealing sensitive information, committing credit card fraud, and even taking sites offline through DDoS attacks. Moreover, they can rent their botnets to other cybercriminals for money.