Multiple DLL Files Quarantined by Avast – False Positive or Real Threat?

Avast Free Antivirus / Premium Security
1

So, in the last week or so, Avast (free version) has been placing several files in quarantine, most of them being files with the .dll extension. At the moment, there are approximately 45 files in quarantine, all of them being .dll, .exe, or .log files. The vast majority are files from common system folders, such as:
C:\Program Files\Samsung\Samsung Settings\OLE23.dll or
C:\WINDOWS\SysWOW64\dlcoer.dll.

All files are being flagged as threats like Win32:FloxLib-A [Trj] or Win32:Pioneer-C.

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image1010×674 66.6 KB

Because of this, whenever I restart my PC, a screen appears saying the following:
WlanAniControl.exe – Bad Image

C:\Program Files\Common Files\System\symsrv.dll is either not designed to run on Windows or it contains an error. Try installing the program again using the original installation media, or contact your system administrator or the software vendor for support. Error status: 0xc0000906

Should I be worried, or is this a false positive? What should I do? Thank you very much!

2

At a first glance it may look a false positive… but,

These 2 names (especially latter) seem file infectors, and quarantined file extensions are exe/dll, there is a strong possibility that it’s a real infection.

Removing file infectors are not my (or this community’s) speciality, unfortunately. All I can advice for now is:

  • Backing up your personal data immediately excluding exe/dll/ocx files
  • Extract some files to somewhere and scan them again to check current detection status (do NOT execute exe files; dll files should be better)
  • Run a full system scan, but make sure automatic action disabled (Settings => Protection => Virus Scan => Full Virus Scan => Automatic actions during scan) to avoid catastrophic false positive or unbootable system
  • After above things done, run a secondary virus scanner (like Microsoft Safety Scanner Download - Microsoft Defender for Endpoint | Microsoft Learn)