What is the term for computers infected with malicious software that can be used to launch attacks?

The term "bot-net" refers to a network of computers that have been infected with malicious software, also known as malware, allowing them to be controlled remotely by an attacker. These compromised computers, often called "bots" or "zombies," are typically used to conduct distributed denial-of-service (DDoS) attacks, spread spam, or perform other malicious activities without the knowledge of the computer’s owner.

The existence of a bot-net is significant in the context of cybersecurity because it highlights the threat posed by exploiting multiple devices simultaneously to achieve scalable attacks and operations that are difficult to trace back to the original source. Bot-nets can encompass thousands or even millions of infected machines, making them a powerful tool for cybercriminals.

Other terms presented in the choices represent different concepts. A "virus cluster" does not hold a recognized meaning in cybersecurity parlance, while "malware network" is a general description that doesn't specifically identify the structured nature of a bot-net. Lastly, a "security breach" denotes an incident of unauthorized access to systems or data, which may result from various attacks but does not specifically refer to a network of compromised devices.