What is a Botnet and How Does it Work?
Botnets are the Swiss Army knife of cybercrime, enabling hackers to execute attacks with greater scale and speed. They can launch distributed denial of service attacks (DDoS), distribute ransomware, steal credit card information, and perform CPU-intensive tasks such as form grabbing or password guessing.
Threat actors use malware distribution methods like phishing emails, software exploits, or firmware vulnerabilities to infect devices with bot malware that enables them to join the botnet. Once an attack begins, compromised devices communicate with a hacker-controlled central server called a command and control (C&C) server to receive instructions.
The structure of a botnet determines how quickly and efficiently commands reach infected systems and its resilience to law enforcement takedowns. The first generation of botnets used a client-server architecture, where the bots connected to a single C&C server. This centralized model is easier for the bot herder to manage, but has a single point of failure; if the C&C is taken down, the entire network is disabled.
Detecting botnet activity is challenging, as the malware is designed for silent persistence. Early warning signs include sluggish applications and slower-than-normal system response times due to background bot activities. Additionally, devices may experience frequent errors such as blue screens and application crashes. Using EDR protection on endpoints and visibility into all devices across your infrastructure, can make it easier to spot bots and respond to threats before they escalate. If a device is infected with bot malware, users will likely need to wipe and reformat the device and run antivirus software.