What defines a Backdoor attack?

A Backdoor attack is primarily defined as a method for unauthorized personnel to bypass security measures in a system or network. This involves creating a secret pathway allowing access without going through the normal authentication process, effectively circumventing established security protocols.

This type of attack can be perpetrated by hackers who gain unauthorized access to systems or by legitimate users who exploit vulnerabilities to maintain access even after the security has been improved. The critical aspect of a Backdoor is its ability to enable bypassing security mechanisms, which aligns with the selected answer.

In contrast, the other options do not accurately capture the essence of a Backdoor attack. For instance, while a Backdoor may facilitate the theft of sensitive data, that is not its defining characteristic; the defining feature is the bypassing of security rather than solely focusing on data theft. Additionally, Backdoor attacks are not limited to those launched by outside hackers; they can also be implanted by internal users who have some level of access to the system. Lastly, the reference to viruses affecting only mobile devices does not relate to Backdoor attacks, as Backdoors can exist across various types of devices and systems, not limited to a specific platform. Thus, the chosen definition provides the clearest understanding of what constitutes a Backdoor