What is a defining characteristic of a Trojan horse?

A defining characteristic of a Trojan horse is that it is malicious software or code running on an end device. Unlike viruses or worms, which can replicate themselves, a Trojan horse disguises itself as legitimate software to trick users into installing it. Once installed, it can carry out harmful actions, such as stealing personal information, creating backdoors, or even facilitating unauthorized access to a device or network.

This characteristic highlights the deceptive nature of Trojans; they often rely on social engineering tactics to convince users to execute them. Users may think they are downloading software for utility or entertainment, but they are inadvertently activating malicious code. Understanding this aspect is crucial for recognizing potential security threats in a network environment and implementing effective protective measures.