What is Botnet and Botnet Attack in Cybersecurity

Botnets have emerged as a considerable threat in the world of cybersecurity, whether it is a simple network or complex, large-scale infrastructures capable of executing sophisticated cyberattacks. The proliferation of Internet of Things (IoT) devices and advancements in artificial intelligence (AI) have significantly amplified everything.

According to a security brief in NZ 2024, botnet-driven Distributed Denial of Service (DDoS) attacks increased by 82%, rising from 90,000 incidents in 2023 to over 165,000 in 2024.

In this article, we are going to discuss the meaning of botnet, how a botnet works, examples, botnet attacks, and so many more. This will also shed light on topics like types of botnet attacks, as well as their detection and prevention.

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What is a Botnet?

A bot refers to an individual infected device, while a botnet in cybersecurity is a network of such infected devices. These botnets are managed through command and control (C2) servers. They are commonly used for activities like DDoS attacks, data theft, and cryptocurrency mining.

It is infected with malware and controlled by a single attacker, called a "bot-herder." While botnets can serve legitimate functions, like managing chat rooms or tracking game points, they become dangerous when misused. Malicious botnets can take control of devices to launch cyberattacks.

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How Do Botnets Work?

Botnets are designed to expand and streamline cyberattacks, giving hackers the ability to scale their operations with minimal resources. A bot-herder begins by targeting vulnerable systems, often using techniques like phishing or click fraud to trick users into downloading an executable file.

Once downloaded, the file runs unnoticed in the background, turning the system into a bot and linking it to a command and control (C&C) channel. The bot-herder can then issue commands using common protocols to avoid detection.

Bot-herders typically write scripts tailored to different operating systems: batch programs for Windows and Bash scripts for Linux. Once the bot is under control, it can carry out a variety of malicious actions, such as:

1. DNS manipulation (DnsMAP): Redirecting domains to a bot-herder-controlled IP.

2. Web injection: Adding harmful code to websites the bot visits.

3. Web filters: Bypassing restrictions or capturing screenshots.

4. Web redirection: Redirecting users to malicious sites.

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What Can a Botnet Do?

Botnets can cause significant harm to both systems and networks in a variety of ways. Here are some of the key actions they can perform:

● Accessing and altering system data

● Stealing personal information

● Sending files and data

● Monitoring user behavior

● Scanning for vulnerabilities

● Running malicious applications

● Botnets are often used for DDoS attacks, data theft, and spreading malware on a massive scale.

Different Models of Botnet

Botnets are organized into structured models that define how infected devices (bots) are controlled. These structures impact the network’s efficiency, scalability, and stealth. The main botnet models are client/server, hierarchical, and peer-to-peer (P2P).

1. Client/Server Model: In this traditional setup, a central Command and Control (C&C) server directs all bots. It’s easy to manage but vulnerable—if the server is taken down, the botnet collapses. There are two variations in this

● Star Topology: All bots connect to one central server—simple, but easily traceable.

● Multi-Server Topology: Uses multiple servers for redundancy and resilience.

2. Hierarchical Model: This model adds layers. A main server controls mid-level bots, which manage lower-level bots. It offers Anonymity for the botmaster, Scalability for managing large botnets, and Resilience against partial shutdowns

3. Peer-to-Peer (P2P) Model: In this decentralized design, every bot acts as both client and server. Bots exchange commands among themselves, making the network highly resilient with no central point of failure and Hard to detect or dismantle.P2P botnets are complex but ideal for persistent and stealthy attacks.

How a Botnet is Made?

Creating a botnet is a multi-step process that allows attackers to silently take control of large numbers of devices. Here's how it typically unfolds:

1. Hackers exploit software flaws, unsecured devices, or human error (e.g., phishing, drive-by downloads) to spread malware.

2. The malware installs silently, hiding in background processes, disabling security tools, and connecting to a command-and-control (C&C) server.

3. Infected devices become bots, unaware they're now part of a botnet.

4. Once enough bots are active, the attacker issues remote commands to launch DDoS attacks, steal data, mine cryptocurrency, or spread further infections.

5. Many botnets self-update and expand autonomously.

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What is a botnet attack?

A botnet attack is a type of cyberattack carried out using a network of infected internet-connected devices, referred to as "bots" or "zombies," which are remotely controlled by an attacker, often called a "bot herder."

These attacks are carried out by exploiting the combined power of many compromised devices to target a victim system, network, or service.

The following are a few types of such attacks:

Botnet examples

Botnet attacks are not uncommon in India. A few examples are given below

1. Necurs Botnet (2017): This botnet was responsible for massive spam and phishing campaigns, impacting systems in India by spreading malware like Locky and Dridex.

2. Mirai Botnet (2016): Aimed at IoT devices, the Mirai botnet caused major DDoS attacks globally, affecting small businesses in India due to the hijacking of unsecured devices.

3. Andromeda Botnet (2017): Known for distributing a variety of malware, including ransomware and banking trojans, Andromeda also targeted users in India.

Detection and Prevention of Botnet Attacks

Botnet attacks can create serious damage for the company as well as the world. The following is a table that summarizes the detection and prevention of such attacks.

Conclusion

With the growing use of IoT and the increasing sophistication of attack methods, botnets are more dangerous than ever, particularly in regions like India, where cyberattacks are rising rapidly.

Understanding how botnets operate, recognizing signs of infection, and implementing prevention strategies—such as regular software updates, strong authentication, traffic monitoring, and user education—are essential to mitigating these threats.

By combining awareness with the right tools and practices, individuals and organizations can significantly reduce their risk and defend against botnet-driven attacks.