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What is a Botnet Attack ? and How to Prevent Botnet Infections. The nature of cybercrime has evolved from its benign origins at the advent of the internet. Botnet attacks have evolved from the dissemination of the first polymorphic viruses all the way to today’s sophisticated botnet attacks. Often when botnet attacks occur, they are massive in scope, and aim to disrupt services, steal credentials, or gain unauthorized access to infrastructure. All in all, botnet attacks involve the infecting and subsequent remote control of a large number of devices for the purpose of further attacks.

The larger the number of infected machines in a botnet attack, the more powerful it is.

What is a Botnet Attack?

First, a botnet attack is a coordinated remote cyberattack launched from multiple compromised devices. Once a device is infected, the malware that is inserted transforms the compromised device into a “zombie bot” that reports back to the botnet’s master. In comparison to malware that just affects a single computer, botnets are more dangerous since they allow cybercriminals to carry out a wide variety of simultaneous attacks. As opposed to a piece of self replicating software, botnet attacks are more like having cybercriminals working within a network.

Botnet attacks are becoming more sophisticated than other forms of malware attacks since they are scaled up or adjusted on the fly to cause even more havoc. This is because a common aspect of botnet-delivered malware is the inclusion of network communication features that enable attackers to exploit the botnet to relay communications with other cybercriminals through the vast array of infected devices.

Basically, botnets help cybercriminals hijack networks, spread malware, and recruit new hosts. Typically, when an attack occurs, it could be mostly for disruption, or it could be a precursor to a subsequent attack.

Types of Botnet Attacks

Brute force attacks

Image source: IDG TECHtalk

A brute force attack is a cyberattack where attackers attempt to guess a password or obtain access to a system through a process of repeated, random guesses. It’s the cyberattack equivalent of trying every code on a keypad to a locked door in the hopes of finally finding the right one.

When it happens, the malware conducting a brute force assault communicates with the compromised service for continuous updates on the status of attempted passwords.

Types of brute force attacks.

Dictionary attacks are the most common type of brute force attack. In this type of attack, an attacker basically scans through a list of potential passwords, usually based on a list of the most regularly used passwords, until they find a match. The rise in the use of automation in cyber hacks has led to a decrease in brute force attacks like these. For example, if your password is a single word, a sophisticated program like Brutus, Medusa, or Ncrack can probably crack it in a matter of seconds.

The reverse brute force attack is another well known type of brute force attack. The attacker begins with a known password (perhaps from a leaked list of passwords found online) and works backward, checking through probable user accounts for matches with the password.

More than 5% of all data breaches are still attributed to reverse brute force attacks, according to some studies.

DDoS (Distributed Denial of Service)

Image source: IDG TECHtalk

A DDoS (distributed denial of service) attack is a malicious cyber attack that is launched with the goal of overwhelming a target with so much traffic that the site or server crashes. This results in the site being inaccessible to users until the DDoS attack is resolved.

DDoS attacks use numerous strategies to target different layers of the Open Systems Interconnection (OSI) model, the structure that governs network connections across the internet.

Types of DDoS Attacks

Application Layer Attacks

The most frequent type of distributed denial of service assault is an application layer attack (also known as layer 7 attacks). In this kind of attack, cybercriminals target a server with so many HTTP requests that it crashes. Often, since it is not easy to tell the difference between valid and malicious HTTP queries, protecting against such attacks is difficult.

Volumetric Attacks

In this kind of attack, the attackers’ goal is to use bandwidth intensive assaults to use up all of their targets’ bandwidth. In this attack, the target server receives an overwhelming influx of traffic as a result of an increase in the volume of malicious data requests. DNS amplification attacks route DNS requests to the IP address of the victim. The attacker then sends fake DNS requests with the victim’s IP address, and the DNS servers respond to the victim instead, consuming the victim’s bandwidth.

Protocol Attacks

Besides, the protocol assaults take advantage of flaws in the protocols that control internet connections. They take place at either the OSI’s third (the network) or fourth (the transport) layer. These attacks sometimes are devastating because protocol updates to fix a vulnerability are often time consuming and cumbersome because internet protocols are global standards.

TCP connection attacks, also known as SYN floods, work by disrupting communication by manipulating the TCP handshakes that start most data transfers over the internet. Spoofed TCP requests are sent by attackers using forged IP addresses. Then the target answers before waiting for the bogus IP address to authenticate the handshake. As more and more failed handshakes pile up, the then target server becomes overwhelmed.

Phishing Attacks

Phishing is an attack in which the attacker disguises himself as a reputable person or organization in order to dupe potential victims into revealing sensitive information or defrauding them of money. The following are the most common types of phishing attacks.

1. Email Phishing

Most phishing attacks are sent by email. In this kind of attack, the fraudster registers an email with a fake domain that mimics a genuine organization and send hundreds of fraudulent generic requests to unsuspecting victims.

2. Spear Phishing

In this kind of attack, the attacker typically already have access to the victim’s name, address, phone number, and possibly even their job details. The attacker uses those details to gain the trust of the victim when sending malicious emails to the victim.

3. Whaling Attacks

Whaling emails often use the trick that a busy CEO needs a favor from an employee. Emails used for whaling attacks are not be as complex as spear phishing emails. However, they’re still effective because they take advantage of employees’ propensity to follow orders from their boss.

4. Smishing and Vishing

In these kinds of attacks, telephones are used. Smishing involves cybercriminals sending fraudulent text messages, while vishing involves a telephone conversation with the victim. Messages purportedly from your bank alerting you to questionable activities are a popular smishing pretext.

Other kinds of phishing attacks include angler phishing, HTTPS phishing, pharming, pop up phishing, clone phishing, and watering hole phishing.

Bricking Attacks

Here, the attacker’s aim in bricking attack, is to make a device inoperable. Well, it happens in multiple stages. In this kind of attack, the device is infected with malware that deletes the device’s contents, causing the device to stop working. This is often done to cover up traces of a primary attack.


This kind of attack involves using spambots to harvest email addresses from websites, guestbooks, forums and other online spaces which require users to provide their email addresses. After acquiring these emails, cybercriminals then utilize them to generate fake accounts and send spam messages.

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Stages of a Botnet Attack

Phase 1: Finding a Vulnerability

Vulnerabilities in software refer to security flaws in an application or operating system. Once discovered, hackers exploit these weaknesses in your system by developing malware that aims to exploit these flaws.

Phase 2: Malware Dissemination

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Step two involves the propagation of malware that has already been developed. To achieve this, hackers frequently employ phishing emails, social network spam, RDP, or drive by downloads from hacked websites. All these delivery methods have one aim, which is to gain access to the devices of several users simultaneously.

Phase 3: Controlling the Devices in the network

The end goal of the attacker is to ultimately get remote control of the devices on the network. Usually attackers aim to infect thousands, if not hundreds of thousands, of machines. This is because once in control, attackers now have a vast network of zombies at their disposal.

Phase 4: The Attack

The fourth and final phase is to attack the target. In this stage, the infected devices are ordered to carry out the attack, and the computers or systems that are targeted are attacked.

This could be a DDoS attack or even ordering the devices to carry out spam attacks.

How to Prevent Botnet Attacks

Image source: IDG TECHtalk

Botnet attacks can be devastating. However, the good news is that they can be stopped. Yes, they can be halted in their tracks or even prevented all together by following appropriate security practices in your network. How? Let’s see how to do it below:

1. Update your systems regularly

Cybercriminals are always working tirelessly to find vulnerabilities in already existing systems. Cyber security experts, on the other hand, are also always working to fix these flaws. This is why updating your operating system and applications frequently is recommended. It’s not worth risking infection from malware or other cyber threats just because you failed to install a software patch.

2. Always monitor your network activity

Keep a close eye out for any suspicious activity on the network. This is far more effective if you have a clear grasp of your typical traffic patterns and how everything normally behaves in your network.

If at all possible, analytics and data collection tools that can automatically detect aberrant behavior, including botnet attacks, should be in place to keep an eye on the network around the clock.

3. Monitor unsuccessful log in attempts

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When it comes to online security, account takeover (ATO) is one of the major concerns for businesses. It is common practice for botnets to be used in brute force testing of massive sets of stolen username and password combinations.

To detect an attack from a botnet, you should monitor the normal rate of failed login attempts and then set up alerts to notify you of any abnormal increases.

However, it’s important to know that these botnet attack detectors might miss “low and slow” attacks that come from a lot of different IP addresses.

4. Make sure you use a firewall

A firewall is the most fundamental component of any security system. However, even though it’s a crucial element of your network security, it is not enough to prevent a botnet attack by itself. This is why it’s important to use it together with other appropriate security safeguards.

5. Give your employees appropriate training

Yes, train your employees on the appropriate security practices that they should follow. Your employees should be trained about botnet phishing attempts, removable media, and physical security concerns as the first line of defence against botnet attacks. This is because when they become aware of the various botnet attacks (for example, phishing attacks), they are better able to identify them as they happen and guard your network against attacks.

6. Invest in anti botnet software

Often, modern botnet detection software can perform real time botnet detection and execute bot mitigation procedures instantly. It is therefore advisable for organizations to invest in these software packages to make sure that their systems are fool proof.

That’s all. Thank you for reading What is a Botnet Attack ? and How to Prevent Botnet Infections. Let’s conclude this article blog.

What is a Botnet Attack ? and How to Prevent Botnet Infections Conclusion

Botnet attacks do not necessarily have to be carried out by sophisticated actors. The Mirai botnet attack of 2016 was carried out by a group of mischievous college students who just wanted to gain an edge in Minecraft. While it may sound benign, it is shocking to note that at its peak, the attack affected over 600,000 devices and resulted in the company losing 8% of its customers.

Botnet attacks are ever present, and they are becoming more sophisticated by the day. However, by carrying out preventive measures, botnet attacks can be halted and even prevented, helping businesses avoid losses that may arise from these attacks.


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Josiah Mutuma

Josiah Mutuma

Josiah is a tech security expert and has been a writer for over 5 years. Follow this blog to learn more on Microsoft and Cyber security.

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