Petko D. Petkov's ongoing research into malicious rigging of media files is now taking aim at Microsoft's ubiquitous Windows Media Player (WMP) software.
The latest discovery revolves around manipulating ".asx" files to display a Web page within the standalone media player.
[The] page will be opened within the Media Player surroundings, not a standalone browser. This in particular is very interesting behavior, which I experimented with for a bit. I found that a fully patched windows XP SP2 with IE6 or IE7 and Windows Media Player 9 (default) will open any page of your choice in less restrictive Internet Explorer environment even if your default browser is Firefox, Opera or anything else you have in place. Let me translate this for you. It means that even if you are running Firefox and you think that you are secure, by simply opening a media file, you expose yourself to all IE vulnerabilities there might be.
On my Windows XP SP2 box with WMP 11, Petkov's proof-of-concept exploits triggered a warning dialog:
Clicking 'Yes' launches the media player with the attacker's Web page displayed in the "now playing" window:
In addition to Petkov's disclosure, there are several Microsoft product vulnerabilities that remain unpatched.