VBS.Haptime.B@mm is a Visual Basic Script (VBS) worm. It infects .htm, .html, .vbs, .asp, and .htt files. It replicates using MAPI objects to spread itself as an attachment. The worm attaches itself to all outgoing messages using the stationery feature of Microsoft Outlook Express.
This is a variant of VBS.Haptime.A@mm. The difference between VBS.Haptime.A@mm and VBS.Haptime.B@mm is the name of the attachment file, which is changed from Untitled.htm to Instlog.htm.
The worm utilizes a known Microsoft Outlook Express security hole so that the worm is executed without having to run any attachment. Microsoft has patched this security hole that eliminates security vulnerabilities in "Scriptlet.TypLib" ActiveX controls. The patch is available at:
If you have a patched version of Outlook Express, this worm will not work automatically.
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