Which term describes the unauthorized access to a network through compromising a system's security?

The term that describes the unauthorized access to a network through compromising a system's security is "Intrusion." This concept specifically refers to instances where an attacker gains unauthorized entry into a system or network, typically with malicious intent, often to steal, manipulate, or destroy data. An intrusion can occur through various methods, such as exploiting software vulnerabilities, bypassing security measures, or using stolen credentials.

In contrast, exploitation refers to taking advantage of a vulnerability in software or systems to achieve unauthorized access or control, which may lead to intrusion but is not the same as the act of entering the system itself. Infiltration, while similar, often implies a more stealthy or gradual process of gaining access rather than a straightforward breach, and it is usually used in contexts like physical security or corporate espionage. Authentication, on the other hand, is the process of verifying the identity of a user or system and is crucial in preventing unauthorized access but does not represent the act of unauthorized access itself.