Windows Defender has been mistaking legitimate Windows files for malicious Trojans

  • The actual threat can perform various malicious actions on infected PCs
  • The detected files range from CPU miners to users’ legitimate Windows files

A bug in Windows Defender is accidentally detecting users’ legitimate Windows files for malicious Trojans, Bleeping Computer reports. Reports of Windows Defender detecting files as Trojan:Win32/Blueteal.B!rfn has recently been making the rounds on the internet. The security protection component of Microsoft Windows has discovered that the detected files range from CPU miners to legitimate Windows files which are actually fake.

A visitor on Bleeping Computer’s forum recently posted that Windows Defender had started to detect their legitimate file as Trojan:Win32/Bluteal.B!rfn.

Multiple other users have also reported experiencing similar issues on a number of Windows 10 1803 systems in which their files were erroneously detected as the BluTeal Trojan as well.

When did the issue start?

According to Microsoft's Windows Defender Security Intelligence site, the Trojan appeared to have been detected on May 18.

The description reads: "This threat can perform a number of actions of a malicious hacker's choice on your PC."

“False alert”

However, Microsoft has clarified that this detection is a false alert and that the issue has already been addressed. It has not specified exactly when the issue was fixed.

As per definition version, the issue seems to have been resolved on Tuesday. Users still experiencing this issue have been advised to check for new updates of Windows Defender and install them.