• A computer gets infected by malware.
• The computer starts working as a bot and logs into a particular Command and Control Server.
• A malicious attacker, e.g., a DDoS attacker, purchases the services of the botnet from the operator of the botnet.
• The attacker instructs the operator to perform a DDoS attack. For example, the attacker can give instructions to redirect unwanted traffic to the target machine.
• When a DDoS attack is performed, the victim’s machine gets flooded with network packets. As a result, the system becomes unavailable for intended operations.

What does a botnet do?

Computers in a botnet can be used in many illegal activities. To give some common examples, they can be used for:

• Sending spam emails.
• Performing DDoS attacks.
• Advertising Adware without the user’s knowledge and awareness.
• Stealing sensitive information through spyware (What is spyware and how to prevent it?).
• Generating false web traffic through Click Fraud for the attacker’s personal and commercial gain and without the user’s knowledge.
• Recruiting more computers in the botnet and spreading computer worms.
• Spreading scareware like ransomware (How to prevent ransomware?).

How to prevent botnets?

There are a couple of countermeasures we can take:

• Prevent your computer from being infected by malware. Do not open suspicious email attachments. Do not click on suspicious links. Install software from trusted sources only.
• Be aware of threats of using Peer-to-Peer File Sharing Software like BitTorrent. You can get more information on the security risks of using P2P File Sharing Software like BitTorrent here: What are the security risks of using P2P File Sharing Software like BitTorrent?
• Update your computer with the latest security patches of software you use. Malware often spreads by exploiting the security vulnerabilities of software.
• Update your anti-virus software regularly.
• Various computer and network security companies have released software to counter botnets. For example, Norton AntiBot helps consumers by shutting down Command and Control Servers or entire IRC servers of a botnet. The use of this software can help you in preventing these attacks.

And remember, awareness always helps. So, keep yourself updated with various security vulnerabilities and how to deal with them. And stay safe and protected.

This was an introductory article on the botnet. Interested readers can find more information on various malware and cyberattacks in the book “A Guide To Cyber Security.”

Security Fundamentals Practice Tests

The Security Fundamentals Practice Tests test one’s fundamental knowledge of cyber security. The practice tests are good for those who are preparing for various certification exams like the CCNA, CCNP, or CompTIA. They are also good for students and IT/security professionals who want to improve their understanding of cybersecurity.