During my daily visit to Richard Bejtlich’ blog, I came information about this flaw in IE which can be exploited to make people believe that they are viewing/visting one site (URL) when in fact they are located on another website. To quote from the “Zap The Dingbat” (who actually discovered the bug)
There is a flaw in the way that Internet Explorer displays URLs in the address bar.
By opening a specially crafted URL an attacker can open a page that appears to be from a different domain from the current location.Exploit
By opening a window using the http://[email protected] nomenclature an attacker can hide the real location of the page by including a non printing character (%01) before the “@”.
Internet Explorer doesn’t display the rest of the URL making the page appear to be at a different domain.
For example, if you click on this button, you will see the URL http://www.microsoft.com in the address bar if you are using IE. But the full address of the URL is http://www.microsoft.com%[email protected]/security/ex01/vun2.htm.
Pretty scary eh.. Just imagine how much this can be abused. People can be tricked into entering their credit card information, usernames/passwords etc.. by mimicking valid sites. And as if though this is not bad enough, Micro$oft hasn’t even released a patch for this yet. So for now, either you type in all addresses manually in the address bar or use trusted saved bookmarks. I would recommend scrapping IE and to start using Mozilla Firebird as your default browser. It is fast, small, adheres to standards and is FREE [as in beer].