Cyber criminals are on the lookout for different ways to access your data through virus, Trojans, hacking, phishing, botnet, etc. They consider small businesses ideal platform for botnet use, and presume that these businesses don’t take much security precautions.

Being part of botnet is so terrifying that it badly affects your business, your partners and customers. It will also create a situation of potential liability. You will not even know that you are part of a botnet. In this article, we will discuss botnets briefly, and learn how to protect computers from them.

What is a botnet?
‘Bot’ comes from robot. When malicious software infect your computer, it becomes a bot. Online fraudsters use your computer to infect a large number of computers. These computers form a botnet. A botnet is, thus, a network of computers that work under the command and control of cyber criminals.

Simply put:

  • A bot/robot/zombie is an infected computer. Cyber criminals distribute malware (Trojan virus or other malicious software) that can turn your computer into a bot that responds to their command.
  • A bot network/botnet/zombie is a group of infected computers or PCs. A single bot is not much benefit to hackers. Therefore, they use a bot as a medium to spread malware to a large number of computers. This group of infected computers forms a network – a botnet.

Purpose of botnet
To get control over the bots to perform automated tasks online without the owner’s knowledge.

What are botnets commonly used for?
Cyber criminals use botnets in numerous ways such as for stealing information, sending spam/junk emails, phishing messages, viruses, spyware to other computers for increasing their network further; click fraud, Adware, flash flux, for DOS (Denial of Service) attack on websites or servers and cause crash.

  • Stealing data: Most people store their sensitive information on their computers such as business or work related documents, personal identifications, and email addresses of all contacts, bank account credentials, telephone numbers, social security numbers and other important data. If your computer is in botnet, criminals can access the information, take loan and purchase under your name, and may commit other frauds.
  • DdoS (Distributed denial of service) attacks: With thousands of zombies, bot masters attack at a time to impair or bring down the website and to disrupt its services by creating loss of connectivity or connection bandwidth.
  • Click fraud: Bot masters use botnets for generating revenue for a website on pay-per-click advertising or for creating web-traffic. In other words, they repeatedly access the site by using user’s computer for personal or commercial gain.
  • Phishing: Botmasters use botnets for hosting phishing sites. They harvest the information from bots by turning them into web server for conducting phishing.

How do botnets enter your computer?
Botnets reach your system via Trojan viruses that carry botnet’s code as the payload (disguised in software or attachment). They can reach your computers in the following ways.

  • Email attachments: When you open infected email attachments or download unverified files or software, botnets access your computer.
  • Infected network: When your system is connected to an infected network.
  • By fake warnings: Criminals provide a link or button with fake warnings such as that your computer has virus. That provokes/scares you into clicking.
  • By malicious websites: When you download the software, videos, and audios from malicious websites.

How to detect botnet infections?
Here are some common signs of botnet infected computers

  • Your outbox will have email messages that you didn’t send
  • Your computer suddenly starts operating slowly or crashes or stops responding frequently
  • Your network or internet connection is unusually slow
  • When you are using the Internet, there is an unknown network activity
  • Your system cannot access a few or any website
  • You will receive more number of spam emails than usual
  • Your firewall alerts you on unknown programs accessing the Internet

How to avoid and protect your computer from becoming part of botnet?
As mentioned earlier, botnets use multiple attacks (DDos attack; phishing; click fraud) so that no single technology is able to protect your computers against them. Packet filtering, port-based and signature-based techniques will not be able to mitigate the evil effect of botnets. This is because botmasters modify the code, shuffle the use of zombie hosts and so on.

Defend yourself

  • Install firewall: Firewall acts as a barrier or protective layer between your computer and the Internet. Note: Don’t turn off your firewall even for a while. There is a potential risk that your system will be infected with malware.
  • Install anti-virus and anti-spyware software: These software scan and monitor your system for known viruses and spyware. When they find, they alert you to take an action.
  • Keep all software up-to-date: Update all the software on regularly. Make sure to subscribe to automatic updates wherever required.
  • Keep an eye on your network traffic: Watch out for unusual traffic. Make sure to keep track of the traffic.
  • Use encrypted passwords: Use encrypted passwords for your home and office networks.
  • Web browsing habits: Don’t click or open or download the files that you receive from unknown sources or the one you suspect.

As the owner of a small business, it is sensible to protect your computers, computer networks against the harmful effects of botnets.