A Bot Attack is a cyberattack carried out using automated software programs (bots) that perform malicious actions at high speed and scale, far beyond what a human could do manually. Bots are scripts or programs designed to execute repetitive tasks automatically; in an attack, they are weaponized to abuse websites, applications, and APIs. Because bots can generate enormous request volumes and operate around the clock, they make many attacks economically viable that would be impossible by hand.
Bot attacks take many forms. Credential stuffing and brute-force attacks use bots to test huge numbers of stolen or guessed username/password combinations against login endpoints, driving account takeover. Web scraping bots harvest content, pricing, or data at scale. Carding bots test stolen payment card numbers. Inventory-hoarding bots hold or buy up limited stock. Scalping bots snap up scarce items or tickets. Bots also power distributed denial-of-service (DDoS) attacks, spam, click fraud, and fake account creation. A network of many compromised, coordinated bots is called a botnet.
What makes bot attacks especially challenging is that sophisticated bots mimic legitimate human behavior – rotating IP addresses, spoofing browsers and devices, solving simple challenges, and pacing requests to blend in. This lets them evade naive defenses and makes distinguishing malicious automation from genuine users difficult. APIs are frequent targets because they expose functionality directly and are designed for programmatic access, blurring the line between legitimate and malicious automated calls.
Defending against bot attacks relies on bot management: analyzing behavioral signals, device fingerprinting, reputation of the source, rate limiting, challenge mechanisms, and machine-learning models that separate human patterns from automated ones. As automation grows more sophisticated – and as legitimate AI agents themselves become heavy API consumers – accurately distinguishing good automation from bad has become a core security challenge.