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Computerworld - Apple today patched a record 62 vulnerabilities in Safari 5, updating the Mac and Windows browser to version 5.0.4.

Wednesday's Safari security update was released at the same time as iOS 4.3, which fixed many of the same flaws.

But Apple's update missed the cut-off for the Pwn2Own contest, which starts today and pits researchers against four browsers -- including Safari, Google's Chrome, Microsoft's Internet Explorer and Mozilla's Firefox -- as the hackers vie for $65,000 in cash prizes.

All but six of the 62 vulnerabilities patched today were accompanied by the phrase "arbitrary code execution," Apple-speak for rating the flaws as "critical."

Unlike other browser makers, including Google, Microsoft and Mozilla, Apple doesn't assign severity rankings to vulnerabilities.

According to Apple's advisory, 57 of the 62 bugs can be exploited by "drive-by" attacks that execute as soon as a victim browses to a malicious Web site with an unpatched edition of Safari.

Most of the vulnerabilities patched Wednesday were in WebKit, the open-source browser engine that powers Safari, and also Google's Chrome. In fact, more than half of the bugs Apple addressed today were originally discovered and reported by Google's own security engineers, or independent researchers who frequently earn bounties from the search company for finding flaws.

Apple also addressed several non-security issues, including one that made sites unstable when they rendered content with multiple plug-ins; another that incorrectly printed Web pages; and others that improved VoiceOver compatibility. VoiceOver is a text-to-speech tool included with Mac OS X that allows the blind and vision impaired to use a Mac and its Safari browser.

Apple last patched Safari in November 2010, when it fixed 27 flaws. Today's update was the largest ever for Safari 5, which Apple shipped in June 2010.

Today's Safari update will not be used by Pwn2Own, however, although today's patches could mean the difference between $15,000 and nothing for some contestants.

According to Peter Vreugdenhil of HP TippingPoint, Pwn2Own's sponsor, the browsers were "frozen" two weeks before today's tip-off, and so the target MacBook Air will not sport Safari 5.0.4. "Exploit development does sometimes rely on certain versions and that is the reason we have frozen the devices," said Vreugdenhil in an e-mail reply to questions today.

But the patches may still play a part. If the vulnerability used by a researcher to hack Safari has been fixed in 5.0.4, TippingPoint will not award the $15,000 prize to him or her, Vreugdenhil confirmed. Instead, the money will go to the first researcher who exploits the "frozen" version of Safari -- in this case 5.0.3 -- using a bug still present in today's update.

"As long as the latest version still has the vulnerability, and the researcher has successfully 'pwned' with the frozen version, he or she will have won," said Vreugdenhil.

Safari 5.0.4 can be downloaded from Apple's site for Mac OS X 10.5 (Leopard), Mac OS X 10.6 (Snow Leopard), Windows XP, Windows Vista and Windows 7. Apple also offered an update to Safari 4.1.3 for customers still running Mac OS X 10.4, aka Tiger.

Mac OS X users will be notified of the new version automatically, while Windows users already running Safari will be alerted by the Apple Software Update tool.

Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer or subscribe to Gregg's RSS feed . His e-mail address is gkeizer@computerworld.com.

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