MSNWorm.BS is a worm that spreads by copying itself, without infecting other files.
It captures certain information entered or saved by the user, with the corresponding threat to privacy:
keystrokes, in order to obtain information for accessing online banking services, passwords and other confidential information.
It uses several methods in order to avoid detection by antivirus companies:
- It terminates its own execution if it detects that it is being executed in a virtual machine environment, such as VMWare or VirtualPC.
MSNWorm.BS does not spread automatically using its own means. It needs an attacking user's intervention in order to reach the affected computer. The means of transmission used include, among others, floppy disks, CD-ROMs, email messages with attached files, Internet downloads, FTP, IRC channels, peer-to-peer (P2P) file sharing networks, etc.