This is important info that everyone use MS Media player (any version). here is the issue I copy & pasted. For MP 6.4 users, it is best to upgrade to 7.1 then install the patch.

Issue:
Windows Media Player provides support for audio & video streaming. Streaming media channels can be configured by using Windows Media Station (.NSC) files. An unchecked buffer exists in the functionality used to process Windows Media Station files. This unchecked buffer could potentially allow an attacker to run code of his choice on the machine of another user. The attacker could either send a specially malformed file to another user & entice her to run or preview it, or he could host such a file on a web site and cause it to launch automatically whenever a user visited the site. The code could take any action on the machine that the legitimate user himself could take.

Affected Software:
Microsoft Windows Media Player 6.4, 7 & 7.1

Patch availability:
Windows Media Player 6.4:
The vulnerability can be eliminated by installing the patch or upgrading to Windows Media Player 7.1 & then installing the patch.
Windows Media Player 7.0:
The vulnerability can be eliminated by upgrading to Windows Media Player 7.1 & then installing the patch.
Windows Media Player 7.1:
The vulnerability can be eliminated by installing the patch.

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