What you do not anticipate until you start having their effects in your systems.
Rootkit is a stealthy type of malware designed to hide itself while in operation. Rootkit is dangerous as it has the ability to operate at deep system level, sometimes before the system loads; and in some cases, at the hardware or firmware levels.
Once installed in the system, (as the name implies), it takes over system operations at Root level. Mingling with systems legitimate files, it can give malicious actors privileged access, allowing them to spy, steal data, or maintain long-term device control.
Traditional antivirus tools may miss them entirely. Some preventive measures include; keeping systems updated, desist from untrusted downloads, use reputable security tools, defense-in-depth, and monitor for unfamiliar behavior and rectify them as soon as possible.
In cyberspace, what you cannot see can hurt you the most.
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