VBS/Mill is a VBScript virus.
Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.
When executed, the worm will first copy itself to following locations:
C:\SeasonGreeting.txt.vbs C:\My Documents\SeasonGreeting.txt.vbs C:\Windows\SeasonGreeting.txt.vbs C:\Windows\System\SeasonGreeting.txt.vbs C:\Program Files\SeasonGreeting.txt.vbs C:\Windows\Samples\WSH\SeasonGreeting.txt.vbs
Then VBS/Mill.F creates a batch file "C:\Windows\System\SeasonGreeting\SeasonGreetingAutoExec.bat" which will delete all files with ".txt", ".exe" and ".zip" extensions files from "C:\My Documents" directory; and files with ".mp3" and ".mp2" files from "C:\My Music" and "C:\My Documents\My Music" directories.
Next the worm modifies the registry in such way that the worm will be executed on the next restart. It also changes Windows' registered owner to "EvilSanta", the product name to "SUX Windows 2004", as well as desktop picture and mouse and keyboard settings.
The worm searches for files with a different extension than ".vbs" from the root of the "C:" drive and from the "C:\My Documents" directory, and if found, creates an additional file with exensions ".txt" and ".vbs" with a big number of spaces between them. This file contains the worm itself
The worm speads itself via different ways, using mIRC and Outlook.
With mIRC it sends itself as "SeasonGreeting.txt.vbs" when an infected user joins an IRC channel.
Finally the worm sends itself using Outlook application. The message that it sends looks as follows:
Subject: You got a Christmas E-Card from you friend!" Body: Wishing you a Merriest Christmas!! ;) You got a Christmas Electronic Card from you friend!! Please open attachment to view E-Card E-Card Brought To You By, f0xCiTY Attachment: SeasonGreeting.txt.vbs
Technical Details: Katrin Tocheva and Sami Rautiainen, F-Secure; December 2000