Tuesday's update was the largest for Apple since March 2008.

"For Apple, updates this size are now becoming the norm," said Andrew Storms, director of security operations at nCircle Network Security.

, which was bundled with the upgrade for Leopard to Mac OS X 10.5.7, and available separately for users of Tiger, plugged holes in BIND, CoreGraphics, Disk Images, Flash Player, iChat, Kerberos, QuickDraw Manager, Safari, Spotlight, WebKit and other bits and pieces of the operating system.

More than a third of the vulnerabilities -- 26 of the 67 -- were labeled with Apple's "arbitrary code execution" description, meaning the flaws are critical in nature and could be exploited to hijack a Mac. Unlike many other vendors, such as Microsoft and Oracle, Apple does not assign a threat ranking to the bugs it discloses.

Over half of the bugs were in open-source components or applications that Apple integrates with Mac OS X, including the Apache Web server and the WebKit browser rendering engine that powers Safari. "I don't see Apple moving at a faster pace," said Storms, referring to previous criticism that the company consistently patches open-source pieces months after the code has been updated by outside developers. "Some of these I remember patching [on Linux] back in December."