The ".sfx" in the name indicates it is a self-extracting archive. When run, it automatically unpacks its contents into a temporary folder and launches the actual setup wizard. Is it Safe or Malware?

Network Interface Card, the hardware that allows your computer to connect to a network.

Because "Realtek" is a trusted name, malware authors often disguise trojans, viruses, or spyware as driver installers. A file named rtk-nic-driver-installer.sfx.exe found on a shady "free driver download" website or delivered via email spam could easily be malicious code designed to steal data or hijack the computer.

rtk-nic-driver-installer.sfx.exe is a self-extracting executable used to install drivers for Realtek Network Interface Controllers (NIC)

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