Technology has revolutionized nearly every aspect of our daily lives. It’s in our homes, our pockets, and the way we conduct business. Digitalization has brought numerous benefits, making the world more connected and efficient than ever before. However, as the saying goes, “with great power, comes great responsibility.” As the adoption of new technologies continues to rise, so do the cybersecurity threats that come with it, putting information security at risk. 

One of the most prevalent and damaging threats today is botnet attacks. This name may sound like something distant, but make no mistake: It can deeply affect businesses and individuals. In this blog post, we will answer some important questions: What is a botnet attack exactly? Why should we be concerned? We will also explain how botnet attacks work and what you can do to protect yourself.

What is a Botnet Attack?

Before diving into the details of recent botnet attacks, it’s important to first understand what a botnet and a botnet attack are. The term “botnet” is short for “robot network,” which refers to a network of compromised computers or devices controlled by a single entity, often without the owner’s knowledge. These devices can include anything from personal computers and smartphones to IoT (Internet of Things) devices, all of which are connected to the internet.

In a botnet attack, cybercriminals use these infected devices to carry out malicious activities, including disrupting services, stealing sensitive data, and gaining unauthorized access to other systems. The stolen data is often highly valuable, such as financial information, personal identifiers, or security credentials. These attacks can be executed on a massive scale, with hundreds or even thousands of compromised devices working in unison to overwhelm systems or networks.

Unlike traditional malware that spreads to a single device at a time, botnet attacks leverage the power of many devices simultaneously. By controlling numerous devices across the globe, the attacker can execute coordinated attacks, making them much harder to detect and mitigate. This is what makes botnet attacks so powerful and dangerous—they can scale quickly and typically occur without warning.

The 5 Main Types of Botnet Attacks

There are various types of botnet attacks, designed to exploit different vulnerabilities. Each of these attacks highlights the versatility and danger posed by botnets, making them a serious concern for both individuals and businesses alike. Here are the key types of botnet attacks:

Brute Force Attacks 

In brute force attacks, the botnet repeatedly guesses login credentials until the correct one is found. These attacks are especially effective when attackers don’t have prior knowledge of passwords and can automate the process to test millions of combinations quickly. This “brute force” method is time-consuming but can succeed if the target doesn’t employ strong password policies or multi-factor authentication​.

Distributed Denial of Service (DDoS) Attacks 

DDoS botnet attacks are some of the most common and disruptive botnet attacks. In this method, botnets overwhelm a server, service, or network by flooding it with excessive traffic, often to the point where legitimate requests can’t be processed. This is a form of cyberattack that can bring down websites or online services. DDoS attacks typically use large numbers of compromised devices—ranging from personal computers to IoT devices—to generate the attack traffic​.

Spam & Phishing

Spam and phishing campaigns use botnets to send large volumes of deceptive emails aimed at stealing sensitive data, such as login credentials. These emails usually appear legitimate, tricking recipients into clicking malicious links or downloading harmful attachments. Successful phishing attempts allow attackers to steal information, further compromising systems and expanding the botnet. Phishing remains one of the most effective methods of gaining access to networks​. 

Device Bricking 

Botnets can also perform device bricking attacks, where the goal is to make a device completely useless. This is typically done by infecting a device with malware that deletes critical files or corrupts its firmware. Once the device is “bricked,” it can no longer function normally. This type of attack often happens in phases: initially, malware is introduced to delete the device’s contents, and then, to further cover the attacker’s tracks, evidence of the infection is erased​.

Cryptojacking

Cryptojacking involves using a botnet to hijack computing resources to mine cryptocurrencies without the victim’s knowledge. The botnet infects devices and leverages their processing power to mine coins, benefiting the attacker. This type of attack is typically unnoticed because it can occur silently in the background. While it doesn’t cause the immediate visible damage of a DDoS attack or data theft, it can significantly slow down systems and increase operating costs due to excessive energy consumption​.

The Recent Botnet Attacks: Top Trends

According to Imperva’s 2024 Bad Bot Report, bad bot traffic rose to 32% of website traffic in 2023, an increase of 1.8% from 2022. 17.6% of the total traffic was driven by good bots, leaving only 50.4% to humans (a decrease of 2.2% from 2022). These numbers are alarming, especially if we take into consideration that 57% of the traffic in 2013 was driven by humans. 

If you are a marketer or business owner, you should be aware that at least part of the traffic you are receiving is driven by bots. And in some cases, this part can be significant. 

The report also reveals that:

• December saw a spike in bad bot traffic (34.2%), likely due to increased attacks and decreased human activity during the holidays.
• 31.7% of all recorded attacks in 2023 were automated threats, with 25% involving sophisticated bots targeting business logic, and 12.4% consisting of DDoS attacks.
• Residential proxies are becoming a favored tool, making bad bot detection more challenging by mimicking legitimate user traffic.
• The US leads in bot attacks globally, accounting for 47% of all attacks, followed by the Netherlands and Australia. Mobile browsers and ISPs are also popular channels for bot operators, with 44.8% of bad bots posing as mobile browsers.
• Financial Services experienced the highest volume of Account Takeover (ATO) attacks in 2023, making up 36.8% of such incidents, followed by Travel (11.5%) and Business Services (8%).

The Most Impactful Botnet Attacks in Recent Years

Botnet attacks continue to evolve, with cybercriminals using them to cause widespread disruption and steal sensitive information. Over the past years, several botnets have made headlines for their significant impact and innovative methods, often targeting IoT devices, critical infrastructure, and online platforms. Below are some of the most notable and impactful botnet attacks in recent history, showcasing how these networks of compromised devices continue to pose a severe threat to cybersecurity.

Mirai and Muhstik

Mirai and its variant, Muhstik, have been persistent threats, continuing to power large-scale DDoS attacks. These botnets primarily target IoT devices such as routers, cameras, and DVRs, exploiting vulnerabilities to compromise and recruit them into their networks.

Mirai has been active since 2016, causing major disruptions across multiple sectors. In 2023, it orchestrated a massive DDoS attack against a major internet service provider, leading to widespread outages that affected millions of users. Its enduring presence highlights its ability to evolve and exploit new vulnerabilities.

Muhstik emerged in 2017, sharing many similarities with Mirai. It leverages default credentials to infect IoT devices and has become a powerful tool for launching DDoS attacks. In recent years, Muhstik has also expanded to include capabilities like cryptojacking, showing its adaptability and threat level.

EternalBot

EternalBot is a sophisticated botnet that has been used to launch a variety of cyberattacks, including DDoS, data theft, and cryptojacking. It’s known for its ability to evade detection, launch DDoS attacks, steal data, and deploy ransomware. This botnet first appeared in 2022 and has been particularly effective due to its ability to evade detection and its advanced capabilities. In 2023, it was linked to several high-profile attacks, including those targeting critical infrastructure, highlighting the severe threat it poses.

Gh0st RAT

Gh0st RAT is a well-known remote access trojan (RAT) that has been used to create botnets for a variety of malicious purposes, including information theft, DDoS attacks, and ransomware deployment. In 2023, a major Gh0st RAT botnet was dismantled, but new variants quickly emerged, showing how resilient and adaptable this threat can be. This botnet is particularly concerning due to its frequent use in targeted attacks against organizations, making it a preferred tool for cyber espionage.

DarkNexus

DarkNexus, a relatively new botnet, has quickly gained notoriety for its powerful DDoS capabilities and ability to adapt to new security measures. In 2023, it was linked to several significant large-scale attacks, particularly targeting gaming servers and online retailers, highlighting its potential for widespread disruption and rapid growth.

Other Notable Botnets

• Mozi: A botnet active since 2019, Mozi focuses on IoT devices, using a peer-to-peer architecture to avoid detection and enhance resilience. It has proven persistent, showing a high infection rate and adaptability.
• Gafgyt: This botnet, targeting IoT devices, has been around since 2014, with its source code becoming public in 2015. It is quite similar to Mirai and it’s often used for DDoS attacks and cryptojacking.

How to Stay Safe from Botnet Attacks? 

Preventing botnet attacks is far easier and less costly than dealing with the aftermath. Recent incidents have highlighted that a proactive approach is essential to safeguarding your organization. Here are some practical steps to fortify your defenses:

How to Prevent Botnet Attacks​?

• Employee Training and Awareness: Educate your employees and partners about the risks of botnet attacks, especially focusing on phishing, which is a common entry point. A well-informed team is your first line of defense.
• Secure Device Onboarding: Only connect new devices to your network after confirming they meet your organization’s security standards. Implement a checklist for evaluating device security before allowing access.
• Regular Software Updates: Keep all systems and devices up to date with the latest security patches. Automate updates whenever possible and schedule regular checks to ensure nothing is missed.
• Credential Management: Change the login credentials for all devices and systems regularly. Use complex passwords and implement multi-factor authentication to strengthen access security.
• Access Controls: Monitor and limit access to your organization’s devices. Only essential personnel should have access to critical systems, and privileges should be granted based on role requirements. Conduct regular audits to verify access levels.

What If You Get Attacked?

Even with the best precautions, no system is entirely immune. Botnets are becoming increasingly sophisticated, so knowing how to respond is crucial:

1. Regain Control Quickly: Act swiftly to isolate and recover any compromised devices. Attempt to disable access to the central server or sever connections to the control servers used by the botnet. This will help contain the damage.
2. Perform a Thorough Malware Scan: Use reliable cybersecurity tools to scan the affected systems for malware. In some cases, a simple software reinstallation can remove the threat. For compromised IoT devices, consider a full factory reset to eliminate persistent malware.
3. Limit the Impact: Focus on containing the attack to prevent further spread. Disconnect affected devices from the network until you are confident they are secure again. It’s crucial to act quickly to mitigate potential data breaches or service disruptions.

Staying Prepared for the Future

The cybersecurity landscape is constantly evolving, and new threats will continue to emerge. Here’s how to maintain strong defenses:

• Continuous Education: Keep everyone informed about the latest threats and defensive strategies. Regular training sessions can ensure your team remains vigilant.
• Traffic and Device Monitoring: Invest in monitoring tools to analyze network traffic and detect unusual patterns. This can help you spot threats early before they escalate.
• Advanced Security Tools: Use specialized cybersecurity solutions that offer features like intrusion detection, network segmentation, and DDoS protection to help safeguard your assets from sophisticated attacks.