What is a bot attack?

A bot attack is a type of attack that uses scripts, called bots, to overload the target with traffic, disrupt a site, steal data, make fraudulent purchases, or other malicious activities.

Learning Objectives

After reading this article you will be able to:

  • Explain what a bot attack is
  • Understand how bot attacks work
  • Learn how to prevent bot attacks

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What is a bot attack?

A bot attack is a type of cyber attack that uses automated scripts to disrupt a site, steal data, make fraudulent purchases, or perform other malicious actions. These attacks can be deployed against many different targets, such as websites, servers, APIs, and other endpoints. The purpose of these attacks can vary, but often includes stealing sensitive information or causing damage to the target’s infrastructure.

Bot attacks can devastate a business, leading to significant and costly downtime for organizations, lost revenue, and reputational damage.

What is a bot?

A bot, short for “robot,” is a software program engineered to automatically perform repetitive and targeted tasks, which can help organizations streamline processes and increase operational efficiency. For example, search engine bots index websites to help provide accurate search results, while customer service bots are designed to answer frequently asked questions and resolve common problems.

Bots can also be designed for malicious purposes and cause significant harm. Malware bots, for instance, can infect computers and steal sensitive information. Bots can also carry out distributed denial-of-service (DDoS) attacks to overwhelm websites with traffic and knock them offline.

Bots are often referred to by other names, such as spiders, crawlers, or web bots.

What are the different types of bot attacks?

There are many types of bot attacks, all of which are designed for a specific purpose. Any actions by a bot that violates a website’s Terms of Services or the site’s Robots.txt rules are considered malicious.

Bot attacks include:

  • Credential stuffing is when attackers use stolen login credentials to gain access to another website. Bots circumvent existing built-in security features in web application login forms by attempting multiple, simultaneous logins from various device types and IP addresses. The goal is to blend in bot attempts with typical login traffic.
  • Web/content scraping is when bots download (or “scrape”) content from a website to use it in future attacks. A website scraper bot sends a series of HTTP GET requests and copies and saves the information — all within seconds.
  • DoS and DDoS attacks are carried out with networks of Internet-connected machines such as computers or IoT devices. Once the network is infected, attackers send remote instructions to each bot to overwhelm the server or network, causing outages and downtime.
  • Brute force password cracking are attacks that use bots to attack and infiltrate protected accounts by trying every possible password combination or cracking encryption keys in order to gain unauthorized access to sensitive data.
  • Click fraud is when attackers target pay-per-click ads to boost search rankings of a webpage via fake clicks. A bot pretends to be a legitimate visitor and clicks on an ad, button, or other hyperlink. By imitating human patterns of behavior, it may trick the platform or service into thinking real users are interacting with the links.

Why do bot attacks happen?

There are many reasons why bot attacks happen. Attackers may use bot attacks to steal financial or personal information, which can then be sold on the dark web for profit. Bot attacks can also be used to attack web services, such as ecommerce sites or social media platforms, causing service disruption and potentially leading to financial losses. In some cases, bot attacks may be used to extort money from victims through ransomware. Lastly, bot attacks may be carried out by hacktivists seeking to disrupt the operations of a particular organization or government entity.

How can companies prevent bot attacks?

There are several strategies companies can use to prevent bot attacks. One effective way to prevent credential stuffing is to implement multi-factor authentication (MFA), which requires users to provide two or more forms of identity before granting access. This makes it so that only authorized users have access to sensitive or confidential information. Adding MFA can prevent credential stuffing or brute force password cracking.

Another way to prevent bot attacks is to curate allowlists and blocklists. Allowlists contain a list of approved IP addresses, while blocklists contain a list of denied IP addresses, such as those associated with bot attacks. This helps prevent malicious bot traffic from ever reaching an Internet property.

Lastly, using bot management software can help detect and prevent bot attacks in real time using behavioral analysis, machine learning, and fingerprinting. Bot management solutions, like Cloudflare Bot Management , use behavioral analysis to identify and detect anomalies in traffic patterns. The software then uses machine learning to compound this data and train bot mitigation programs to recognize malicious activity.

With the data available — up to hundreds of billions of requests per day — Cloudflare Bot Management is able to effectively identify good bots from bad bots, while helping defend Internet properties from a wide range of bot attacks. Learn how Cloudflare Bot Management helps spot and block malicious bot behavior.