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Alert level: Severe Detected with Windows Defender Antivirus
Also detected as: TR/Rootkit.Gen (Avira) BackDoor.Maxplus.2 (Dr.Web)
Trojan:WinNT/Sirefef.C is the detection for a driver component of Win32/Sirefef - a multi-component family of malware that moderates your Internet experience by changing search results and generating pay-per-click advertising revenue for its controllers. The family consists of multiple parts that perform different functions, such as downloading updates and additional components, hiding existing components, or performing a payload.