There has been wide coverage of a Windows animated cursor exploit; MS does not seem to have patched it yet. In a blog on ZDNet today, over 150 sites were reportedly exploited using this animated cursor exploit.  The blogs says:
The vulnerability is caused by an unspecified error in the way Windows 2000, XP, and Vista handles animated cursors. Animated cursors allow a mouse pointer to appear animated on a Web site. The feature is often designated by the .ani suffix, but attacks for this vulnerability are not constrained by this file type so simply blocking .ani files won’t necessarily protect a PC. Successful exploitation can result in memory corruption when processing cursors, animated cursors, and icons.
If you are concerned about this you should contact your server management company to have your server patched as soon as possible again this expoit.
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