Threat Description



Category: Malware
Type: Worm
Platform: VBS
Aliases: CoolNot


VBS/CoolNot is a worm, similar to the VBS/LoveLetter.


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


VBS/CoolNot.A uses Outlook to sent itself to all recipients in every address book. The message that it sends is as follows:

 Subject:    Cool Notepad Demo     Body:       Hey check out this text file I sent it will do     something neat in notepad.     Enjoy :-)     Attachment: COOL_NOTEPAD_DEMO.TXT.vbs  

It copies itself to the Windows System directory as "COOL_NOTEPAD_DEMO.TXT.vbs" and adds a key to the registry so that it will be executed next time the system is restarted.

Then the worm replaces the "script.ini" file from the mIRC installation directory. The worm uses this modification to send itself to those users who join to the same channel as the infected user. In addition, the worm will join to the "#virus" channel and send a message "Cool Notepad Demo" to that channel.

As a payload, the worm adds a registry key that will hide the desktop after the system is restarted. This registry key is:


To restore your desktop, please download and execute the following registry file:

Description Details: Analysis: Katrin Tocheva and Sami Rautiainen, F-Secure


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