http://zdnet.com.com/2100-1105-5350010.html
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Apple Computer released an update to its Mac OS X operating system on Tuesday to fix 15 security issues in the software.
Many of the problems are flaws in the operating system's underlying open-source software, including a critical flaw in the Kerberos authentication system--software that can act as a gatekeeper for computer networks. The patch is available for Mac OS X 10.3.5 and Mac OS X 10.3.4, and also fixes issues in Mac OS X 10.2, known as "Jaguar."
The patch fixes software flaws that could enable an attacker to crash or freeze the Apache 2 Web server, run software by utilizing Apple's Safari Web browser or expose the password store used by the network. Security information provider Secunia/news:link> ranked the Kerberos threat as "highly critical," its second-highest danger rating.