A rootkit is a type of malicious software (malware) or a collection of software tools designed to give unauthorized users—typically cybercriminals—privileged (administrator or “root”) access to a computer or network, while actively hiding its presence and the presence of other malicious activities or software. The term “rootkit” combines “root” (the highest level of access in Unix-like systems) and “kit” (a set of software tools). Rootkits are typically installed after attackers gain privileged access, often through exploiting software vulnerabilities, phishing, or social engineering tactics. They can also be bundled with other software or downloaded from untrustworthy sources.