Risk: High
Apple's latest security advisory patches 31 OS X and 12 QuickTime flaws, which Secunia has ranked as 'highly critical'. Although Apple doesn't rate its flaws by level, high level risks typically indicate that users could either launch a Denial of Service attack or gain full remote access of an affected system. The QuickTime flaws allow an attacker access to Mac and Windows operating systems if a specially crafted media file in certain formats (including JPEG, QuickTime, Flash, MPEG4 and AVI) is opened.
Mac users have been recently criticised by McAfee for becoming complacent about security issues - research found that flaw discovery rates have increased by 228% since 2003. Generally speaking, flaws aimed at Apple programs and products do seem to be significantly rarer than those aimed at Windows products, but this may have made Apple users complacent and lax with securing their computers.
The patches are available from Apple's downloads page at http://www.apple.com/support/downloads/