What Is A Botnet (And How Are They Used)?

Cybersecurity is an extremely important topic for any individual with an internet connection – and, unfortunately, we need to accept that it is not going away.

As our lives become ever more connected and our homes increasingly networked, we’ll all need to remain vigilant and attuned to the dangers.

Botnets are a growing concern for many people, and rightly so. Knowing what they are and how they work is the first step in protecting yourself and your computers against them. 

What Are Botnets?

What Is A Botnet (And How Are They Used)?

Botnets are networks of computers controlled by hackers. A cyber criminal, or an organized group of them, use them to steal personal information or do damage to companies through cyberattacks. 

Bots make up a large part of a botnet. These bots are programmed to perform certain tasks. A botnet can be used to send spam emails or spread viruses.

The term “bot” is short for robot, which in turn comes from the name of an early mechanical device that could move on its own. 

Today, a computer program called a bot is designed to mimic human behavior and interact with other programs or people.

It may do many things on an infected computer – download files, search online, play games, or even commit crimes like sending out spam email messages or spreading malware to other vulnerable devices.

The first thing you should know about a botnet is that it’s not a single entity. Instead, it’s made up of hundreds of thousands of individual PCs connected together through the Internet.

Each PC is infected with software that allows the hacker to control it remotely. This software, known as “malware,” includes keyloggers, spyware, adware, and more.

Botnets are typically used by many cyber criminals for two purposes: to distribute spam or malicious code, and to launch distributed denial-of-service attacks against websites. But they’re also increasingly being used to take over PCs for illegal activities.

How Do Botnets Work?

A botnet is a network of compromised computers that work together to accomplish a task. In most cases, this means that the botmaster controls all the computers in the network. They do so by using one or more of these methods:

1. Malicious Software.

2. Social Engineering.

3. DDoS Attacks.

4. Paying Users.

5. Exploiting Vulnerabilities.

6. Hijacking Computers.

7. Stealing Data.

Malicious Software

When a user downloads a malicious file or opens malicious email attachments, he or she unwittingly installs malware onto his or her machine. 

Some botnet malware is designed to look like legitimate applications, such as a word processor or a web browser. Others masquerade as antivirus software. They can install themselves without the user’s knowledge. 

Once installed, the malware gathers sensitive data, including passwords, credit card numbers, bank account details, and social security numbers.

Social Engineering

Most users don’t think twice before clicking on links sent to them via email or instant messaging. Unfortunately, many of those links lead to sites where malware is downloaded into their machines. 

If a person clicks on a link while logged into a website, the site will often store the username and password that was entered during the session.

That way, when the same person returns to the site later, he or she won’t have to log in again.

When a user visits a compromised website, he or she might see a pop-up window asking if the visitor wants to view a video. Clicking on the button inside the window will start downloading malware to the victim’s system.

DDoS Attacks

Many cybercriminals use botnets to launch Distributed Denial-of-Service attacks against websites. With a DDoS attack, hackers flood a target site with traffic until it becomes unreachable. Most DDoS attackers use botnets to carry out their attacks.

Payment Systems

Some botnets are created specifically to harvest payment card details. Card skimmers are small devices that criminals attach to ATMs and point at customers’ cards.

The skimmer reads the magnetic strip on the back of the card and sends the data to the attacker.

Exploiting Vulnerabilities

In some cases, hackers can exploit vulnerabilities in operating systems and other programs to gain access to a computer. For example, there are several ways that Windows XP users can be tricked into installing a virus.

Hijacking Computers

Sometimes, hackers hijack computers by taking advantage of weaknesses in the networks that connect them. When a computer connects to the Internet, it uses a protocol called TCP/IP.

Hackers can intercept messages between computers and redirect them to another computer.

Stealing Data

Theft is probably the most common reason why people get hacked. Many times, hackers steal usernames and passwords from online accounts. They then use those credentials to break into financial institutions, government agencies, and businesses.

How To Prevent Botnet Attacks

The CSDE recommends that companies install software updates as soon as possible, and automatically if possible. Updates are important because bots use unpatched vulnerabilities.

Vendors are getting better at checking for compatibility and other problems before releasing an update. 

Some enterprises don’t want to wait until they’ve checked for compatibility and other issues, but instead want to do the updates themselves. Enterprises that don’t automatically update should consider doing so. 

Hardware devices should be updated automatically. Legacy products, both software and hardware, may no longer be supported.

Enterprises should lock down access to prevent further infection. Botnets spread via credentials, so locking down access is key.

Companies should use physical keys for authentication instead of relying on passwords or other forms of digital identification. This will prevent hackers from stealing your data.

Your company should consider using 2FA (2-Factor Authentication) to protect your accounts. You can also use a cloud service provider to store your sensitive data.

Attackers are extremely capable. They can add stress to your networks from a number of different sources. You need to protect your network from DDoS attacks by adding more security measures. 

Anti-botnet guides often recommend that enterprises should consider deploying advanced analytics to secure users and data, ensure that security controls are properly set, and use network segmentation and architecture that securely manages traffic flows.

 Some Types Of Botnets And Viruses

Nitol – This is an evolving DDoS botnet family that periodically modifies itself. It mainly operates in China. 

Once infected, its malware usually connects via TCP sockets and then sends performance information about the victim’s computer. 

Microsoft security researchers discovered that Nitol-infected PCs were being sold in large numbers in China. In 2013, an Imperva report revealed that Nitol was the most widespread botnet, accounting for 59.2% of all attacking botnet addresses.

Trojan.Linux.Spyware.A – This uses Linux systems to send data back to a remote server. It might be used by hackers to steal passwords or credit card numbers.

Cyclone – This is a DDoS toolkit that uses IRC channels to communicate with command servers. It steals FTP credentials using FileZilla. It kills off other bots on infected hosts, and steals them from FileZilla.

Pushdo/Cutwail – This is a bot network that sends out spam emails. It uses a Trojan program known as Pushdo to do this. 

In early 2010, Cutwail changed tactics and began using DDoS attacks instead of spamming. This attack targeted hundreds of websites, including the CIA, FBI and Twitter. The botnet also affected computer users in over 50 countries.


Botnets are dangerous because they can be used by hackers to launch cyberattacks. They are also used to steal money and data. 

Most people do not know how to protect themselves or their companies from these threats. To avoid being attacked, companies need to make sure that they have proper security measures in place.

Dale Williams
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