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  3. JS.Fortnight.B


Risk Level 1: Very Low

March 19, 2003
February 13, 2007 11:44:37 AM
Also Known As:
JS/Fortnight.b@M [McAfee], JS.Fortnight [KAV], JS_FORTNIGHT.C [Trend]
Trojan Horse, Worm
Systems Affected:
Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows XP

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.

Antivirus Protection Dates

  • Initial Rapid Release version March 20, 2003
  • Latest Rapid Release version September 28, 2010 revision 054
  • Initial Daily Certified version March 20, 2003
  • Latest Daily Certified version September 28, 2010 revision 036
  • Initial Weekly Certified release date March 26, 2003
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

Threat Assessment


  • Wild Level: Low
  • Number of Infections: 50 - 999
  • Number of Sites: More than 10
  • Geographical Distribution: Medium
  • Threat Containment: Easy
  • Removal: Easy


  • Damage Level: Low


  • Distribution Level: Low
Note: On May 14, 2015, modifications will be made to the threat write-ups to streamline the content. The Threat Assessment section will no longer be published as this section is no longer relevant to today's threat landscape. The Risk Level will continue to be the main threat risk assessment indicator.
Writeup By: Douglas Knowles

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