Threat Description

Virus: ​W32/Drowor.A


Category: Malware
Type: Virus
Platform: W32


Drowor.A is a Windows file appending virus that infects executables in all drives found including network drives.


Automatic action

Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.

More scanning & removal options

More information on scanning or removal options is available in the documentation for your F-Secure security product on the Downloads section of our Home - Global site.

You may also refer to the Knowledge Base on the F-Secure Community site for more information.

Contact Support

For further assistance, F-Secure customers can request support online via the Request support or the Chat forms on our Home - Global site.

Technical Details

Drowor.A is a Windows file appending virus that infects executables in all drives found including network drives.Upon execution, this virus checks to see if it is already running in memory by elevating its privileges and enumerating currently running processes on the affected machine.It then creates and executes a copy of itself as:

  • %windows%\system\internat.exe.

It drops a hidden copy of itself, setup.exe, in the root directory of discovered drives. This includes network drives. It creates an autorun.inf alongside of this setup.exe that may trigger and execute the file. It Infects by appending itself in Windows executables, adding a section named ".ice" in the infected files.Drowor.A creates a text file list of Windows executables in the discovered drives to a hard-coded path:

  • C:\WINDOWS\win.log

Drowor.A attempts to accesses a file from:


The URL is currently unavailable.


Database: 2007-03-11_01

Detection Type: PC F-Secure Anti-Virus detects this malware with the following updates:

Detection Type: PC
Database: 2007-03-11_01

Description Created: 2007-03-12 16:50:32.0

Description Last Modified: 2007-03-12 17:38:35.0


Suspect a file or URL was wrongly detected? Submit a sample to our Labs for analysis

Submit Now

Give And Get Advice

Give advice. Get advice. Share the knowledge on our free discussion forum.

Learn More