Short for “robot network” a botnet is a network of computers or multiple devices that are under control of an attacker or attacking party. When a system or computer is compromised it becomes a “bot” and is controlled by the “bot-herder” or “bot-master.”
How does a botnet attack work?
A botnet attack involves compromising a large number of devices with malware. This can be done through a variety of methods including phishing, smishing, brute force attacks, DDoS attacks, and more. Typically, the goal of the attacker is to hide the malware, making it difficult for the user to know they have control over their system. This will allow attackers to operate within a network and infect more systems without being detected.
Once a device has been infected, the attacker connects it to a command-and-control (C&C) server to carry out more attacks, steal data, or send spam emails. In a botnet attack, it is common for the botmaster to conduct a DDoS attack where the attacker floods a server with traffic, making it inaccessible to users.
Types of botnet attacks
A botnet itself refers to multiple compromised devices. However, threat actors can leverage multiple devices to launch a variety of large scale attacks. These attacks include:
DDoS attacks: Distributed Denial of Service, DDoS attacks are a large scale cyber attack that uses multiple IP addresses to flood a server. This ultimately overwhelms the server and can be detrimental to companies who participate in e-commerce or run most of their business activity through servers connected to the internet.
Spamming: This is the process by which a threat actor sends spam messages containing malicious content. The messages usually come in masses, meaning they are trying to reach as many accounts as possible in order to fool just a few victims into downloading or clicking malicious materials.
Click fraud: This is a method of disrupting a businesses digital ads. Often businesses purchase digital ads and get their return in the form of clicks. The attacker will conduct fraudulent clicks on an add repeatedly, exhausting the ad purchasers clicks.
Keylogging: This process involves a threat actor monitoring keyboard activity of a user without the users knowledge. The threat actor will see which keys are being clicked in order to steal login credentials and ultimately compromise a users account.
Cryptojacking: A threat actor will hijack a device and use it to mine cryptocurrency. They do this because mining crypto is extremely expensive and the acquisition of crypto currency is untraceable.
Brute force attacks: A brute force attack involves trying to guess the correct login credentials to an account. If there are multiple devices compromised, like in a botnet attack, the likelihood of finding the correct login information increases.
Why are botnet attacks dangerous?
Botnet attacks can be persistent, meaning that even when a compromised device is found, the attacker can continue to operate. This is because it is likely that the attacker has compromised multiple devices in the network at this point. Likewise, the attacker can replace the malware and encrypt communication between the infected devices and the C&C, making it very difficult to remove the infection.
It is possible for the bot-master to compromise thousands, if not more, devices at a single time. They can sell access to these devices or launch large scale attacks that can be extremely troubling for security teams to deal with.
Like most successful cyber attacks, a botnet attack can be highly detrimental to an organization. Financial losses, data breaches, and disruption of business activity/services are just some of the ways organizations can be harmed if they fall victim to a botnet attack.
How to protect against a botnet attack
The best way to stop a botnet attack is to have preventative cyber security measures in place. While detection and response systems are useful for breaches, a botnet can be difficult to deal with once it is established in the network. Preventing a cyber attack from happening at all is the best defense. Some advanced security solutions include attack path analysis, attack surface management, and penetration testing.
Other methods include implementing antivirus or anti-malware software, keeping your software up to date, using strong passwords, staying on top of current threat actor tactics, techniques, and procedures (TTP), having detection and response systems in place for your organization, and regularly monitoring your network traffic.
How AI cyber security can stop botnets
There are several affordances of AI-powered security that can help fight against a botnet attack. AI powered security solutions can detect and block ransomware in real-time, using machine learning algorithms to identify and respond to threats before they can cause damage or spread through to multiple devices. Some AI security systems have autonomous detection and response systems that have the capability to stop an attack from escalating by identifying and containing infected devices.
Similarly, AI can be used to analyze network traffic and identify unusual patterns or behaviors that may indicate a ransomware attack in progress. If this AI takes a Self-Learning approach, it can help organizations detect and respond to attacks quickly, reducing the impact of the attack by identifying activity in the digital estate that deviates from normal behavior.
Having a human lead team alone makes it difficult to process and classify large amounts of data which AI can be used to help organization and identify vulnerabilities allowing security teams to prioritize and strategically plan out their security efforts.
Most common botnet distribution is via email. Self-Learning AI (Darktrace/Email) is able to identify advanced anomaly indicators. Or a botnet attack is successful, Self-learning AI will detect the presence of the new user agents being used, the download of the botnet itself or the repeated (or low & slow) connections to the C2 infrastructure.
Darktrace PREVENT allows the security team to identify, prioritize, and test vulnerabilities, reducing risk and hardening defenses both inside the organization and outside on the attack surface – continuously and autonomously.
Darktrace DETECT delivers instant visibility into the most advanced threats like botnet attacks by understanding what’s normal in your organization, to identify what’s not.
Darktrace RESPOND delivers autonomous, always-on action to contain and disarm attacks within seconds. When a threat like malware is detected, RESPOND leverages Darktrace’s understanding of “self”, to pinpoint signs of an emerging attack, stopping malicious activity, while allowing normal business to continue.