JS.Fortnight.B is a Trojan Horse that drops a file, which is inserted into the default Microsoft Outlook Express signature. Then, every time you send email using Outlook Express, the message will contain code attempting to open a specific Web site when the message is opened.
JS.Fortnight.B also changes the Internet Explorer security settings. It also configures the Web Browser to prepend all the URLs with a specific URL.
This script exploits a known vulnerability in the Microsoft Virtual Machine ActiveX component. For additional information on this vulnerability, refer to: http://www.microsoft.com/technet/treeview/default.asp?url=/technet/security/bulletin/MS00-075.asp
Security Response recommends installing this patch to remove this security vulnerability.
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