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Microsoft Security Intelligence
Published Mar 15, 2011 | Updated Aug 22, 2017


Detected by Microsoft Defender Antivirus

Aliases: Win32/Winwebsec (other) Rogue:Win32/Winwebsec (other) System Tool (other) MS Removal Tool (other)


System Tool is a variant of Win32/Winwebsec - a family of programs that claims to scan for malware and displays fake warnings of "malicious programs and viruses". They then inform the user that he or she needs to pay money to register the software to remove these non-existent threats.

Win32/Winwebsec has been distributed with many different names. The name used by the malware, the user interface and other details vary to reflect each variant's individual branding. The following details describe Win32/Winwebsec when it is distributed with the name "System Tool".

To detect and remove this threat and other malicious software that may be installed on your computer, run a full-system scan with an appropriate, up-to-date, security solution. The following Microsoft products detect and remove this threat:
For more information on antivirus software, see