What is a Botnet?
A botnet is a network of computers and devices infected with malware that allows attackers to remotely control them. Cyber criminals use botnets to carry out various malicious activities, such as DDoS attacks, spam campaigns, and data theft.
Malware spreads through phishing emails, software vulnerabilities, and exploit kits distributed on dark web marketplaces. When clicked or downloaded, these tools install malware on the user’s device, turning it into a bot. Bots operate silently in the background, awaiting instructions from the bot herder. Once a bot is infected, it can perform a variety of tasks ranging from reconnaissance to attacking other devices in the botnet.
Attackers can control large numbers of compromised devices in botnets using centralized command and control (C&C) servers. These servers connect to each infected device and send commands ranging from reconnaissance to launching attacks.
Many security researchers and law enforcement agencies track C&C servers, and attempt to disrupt their operations by blocking their channels and seizing the infrastructure and domains used by attackers. However, cybercriminals quickly rebuild their networks. They also develop new variants of the malware and techniques to evade detection and removal.
Educating users on the dangers of clicking suspicious links in email, text, or social media posts can reduce the chances of their devices becoming part of a botnet. Implementing strong ingress and egress filters that prevent traffic from entering or exiting the network based on suspicious behavior can help to mitigate botnets as well. Changing default passwords on connected devices can also help to secure them.