Which type of attack utilizes multiple compromised systems to overwhelm a target system?

The attack that utilizes multiple compromised systems to overwhelm a target system is known as a Distributed Denial of Service (DDoS) attack. In a DDoS attack, an attacker exploits a network of compromised computers, often referred to as a botnet, to flood a target server, service, or network with excessive traffic. This overwhelming influx of requests makes the target system unable to efficiently process legitimate requests, leading to a denial of service for genuine users.

DDoS attacks can take various forms, including volumetric attacks, protocol attacks, or application-layer attacks, but the common element is the use of multiple sources of traffic to impair the target. This characteristic distinguishes it from other types of attacks, such as ransomware, which specifically involves encrypting files for ransom, or a man-in-the-middle attack, which involves intercepting and altering communications between two parties. A Trojan horse, while malicious, typically disguises itself as legitimate software rather than employing a network of systems to launch a large-scale attack.