A rootkit is a program or a set of programs designed to obscure the fact that a system has been compromised.

For Windows operating systems, the term rootkit stands for a program that infiltrates the system and hooks system functions (Windows API). By hooking and modifying low-level API functions, such malware can effectively hide its presence in a system. Moreover, rootkits as a rule are able to conceal in the system any processes, folders and files on a disk as well as registry keys described in its configuration. Many rootkits install own drivers and services (hidden as well) into the system.

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