Category :


Type :


Aliases :

MultiDropper-LA, Neblso.A, W32/MultiDropper-LA


Files detected as MultiDropper-LA drop already detected worms into the system's temporary files folder and execute them.


We have received four samples which, upon being executed, will drop two files into the system's temporary files folder. The dropped files are old malware, already detected by F-Secure Anti-Virus.

A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:

  • Check for the latest database updates

    First check if your F-Secure security program is using the latest updates, then try scanning the file again.

  • Submit a sample

    After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.

    Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.

  • Exclude a file from further scanning

    If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.

    Note: You need administrative rights to change the settings.

Technical Details

All the variants we received drop two files. We now provide their filenames and current detection results.

  • %Temp%/document.txt .exe Infected: W32/NetSky.P@mm
  • %Temp%/your_details.exe Infected: I-Worm.Sobig.f
  • %Temp%/document.txt .exe Infected: W32/NetSky.P@mm
  • %Temp%/msblast.exe Infected: Worm.Win32.Lovesan.a
  • %Temp%/document.txt.jpg Infected: W32/NetSky.P@mm
  • %Temp%/ Not an executable
  • %Temp%/your_details.exe Infected: I-Worm.Sobig.f
  • %Temp%/msblast.exe Infected: Worm.Win32.Lovesan.a

Afterwards those files are run, triggering all the known effects produced by those worms.