A botnet is a collection of compromised computers that cooperate to accomplish the objectives of an attacker. The name, which combines the terms “robot” and “network,” suggests that the different compromised computers inside the network have some degree of autonomy.
How Does a Botnet Work?
An attacker creates a botnet by gaining control of a large number of networked computers. While it is feasible to develop a botnet using inexpensive processing power, such as cloud infrastructure, botnets are often created via infecting machines with software. Botnets frequently target devices with known security flaws, such as Internet of Things (IoT) platforms.
This virus deployed on the machine will look for instructions from the botnet’s command and control (C2) infrastructure. Botnets can employ several types of C2, such as data posted on websites, social media channels, responses to DNS searches, and so on. Following instructions from a C2 server, the botnet will execute those commands. Botnets can be employed in a variety of assaults, some of which may require further connection with the C2 server. However, in rare situations, the botnet may also send information back to the C2 server.
Botnets: How Do They Work?
Botnets are intended to automate a variety of assaults, making them easier, cheaper, and more scalable for cybercriminals to execute. Botnets frequently play a role in several stages of the cyberattack lifecycle, including:
Vulnerability Scanning: Malware and other assaults typically begin by exploiting a weakness in the target system. Botnets can be used to scan for susceptible systems that can be exploited and used in subsequent assaults.
Malware Delivery: Botnets are frequently built to be self-replicating, enhancing the power and reach of the malicious network. After detecting a vulnerability in a targeted system, a bot may exploit it to infect the system with the botnet.
Multi-Stage Attacks: Botnets are occasionally used to transmit malware other than their own. For example, the botnet could download and install a banking malware or ransomware onto the victim machine.
Automated Attacks: Once installed on a computer, the botnet can be used to launch a variety of automated attacks. In general, these are untargeted attacks that take advantage of the botnet’s scale.
Types of Botnet Attacks
Botnets are designed to execute assaults that are simple to automate and scale. The following are some frequent forms of assaults that botnets could be used to perform:
Distributed Denial of Service (DDoS): DDoS attacks are intended to overwhelm a target with traffic from numerous sources, preventing it from handling valid requests. DDoS attacks are among the most popular uses of botnets.
Password Attacks: Credential stuffing and other automated password guessing attacks use compromised credentials, dictionaries, or brute force searches to determine online account passwords. If legitimate credentials are discovered, the attacker may utilize them in a number of attacks.
Phishing: Botnets can be used to facilitate phishing assaults. For example, a botnet may employ infected PCs to send phishing and spam emails, expanding the scope of the harmful email campaign.
Cryptojacking: Cryptojacking exploits the processing capabilities of infected PCs to mine bitcoin. The profits of this mining activity go to the attacker, allowing them to profit at the victim’s expense.
Financial Fraud: Credit card information is often sold on the dark web or acquired as a result of data breaches. Bots can be used to validate data or to commit financial fraud through compromised accounts.
Ad Fraud: Websites get money based on how many times an ad is viewed or clicked. Botnets can commit click fraud by pretending to be legitimate users and clicking on adverts to generate cash for harmful websites.
Scalping: Some large events offer tickets online, with a limited supply available. Bots can purchase tickets faster than humans, allowing their operators to resell them at a profit on the secondary market.
