Apple today released QuickTime 7.1.5 which delivers numerous bug fixes and addresses critical security issues.
This update is recommended for all QuickTime 7 users.
QuickTime 7.1.5 is available via Software Update and also as a standalone installers:
• QuickTime 7.1.5 for Mac (41.4MB): System Requirements: Mac OS X 10.3.9 or later
• QuickTime 7.1.5 for Windows (18.6MB): System Requirements: Windows XP with Service Pack 2, Windows 2000 with Service Pack 4
Vista remains unsupported, it seems.
Apple releases iTunes 7.1 for Mac and Windows – March 05, 2007