VBS/Mcon is a worm that spreads via open network shares and mIRC.
Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.
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.
Variant:Mcon.A
When the worm is executed, it first checks if the "Fonts" subdirectory in the Windows installation directory contains the worm. If the file is not found, the worm copies itself there using a filename "ttfloader.vbs". Then the worm executes the copy from the "Fonts" directory and deletes the original file.
If the original file was not named "ttfloader.vbs" or was not executed from the Windows' Startup directory the worm shows a message box with the following text:
FILE I/O ERROR
Next the worm will add itself to the registry, so it will be executed each time when the system is restarted.
Depending an a random number, the worm may change the Internet Explorer page to www.zonelabs.com.
The worm goes trough all drives in the system and if the drive is a local fixed disk, it copies itself to the root of the drive and to the following directories:
pub ftproot wwwroot
or if the name of the directory contains any of the following strings:
my download upload share game warez
The worm copies itself using a random file name taken from user's Recent directory, with a number of spaces and a ".vbs" extension appended to it. An attempt is made to hide the file by changing the file attributes as well.
It also removes following directories, if found:
chode foreskin dickhair
If the drive is a network or removable drive, then VBS/Mcon.A copies itself to the root of the drive, and any directory that contains one of the following strings:
my share download downloads
Also, if Windows' Startup directory is found, the worm copies itself there as "ttfloader.vbs".
The worm deletes following files regardless of the drive
mscfg.exe ashield.pif netstat.pif network.vbs mscfg.vbs winsock.vbs a24.vbs
If VBS/Mcon.A founds a mIRC installation directory, the worm copies itself to the Windows' Fonts directory using name "sndload.vbs" and replaces the "script.ini" file with its own.
Next the worm chooses a random IP addess within some limits and uses the ping utility to check if a machine responds at that address. If the machine exist, it attempts to connect to each share on the remove machine.
If the connection is established, the worm will go through all directories in the shared drive copying itself there in the same way it does with removable and network drives above.
Variant:Mcon.B.
VBS/Mcon.B is modified variant of VBS/Mcon.A. The filename, that the worm uses in Windows' Fonts directory is changed to "ttfloads.vbs".
Additionally this variant copies itself to the Windows' System directory as "ttfload.dll".