The Mac OS X was released by Apple in 2001 as a solid UNIX-based Operating System. Although Mac OS X has security features implemented out of the box such as built-in personal firewall, un-necessary services turned off by default and easy ways to increase the OS security, the user still faces many vulnerabilities.
Mac OS X also includes the Safari web browser. Multiple vulnerabilities have been found in this browser and in certain cases exploit code has also been posted publicly.
Apple frequently issues Mac OS X cumulative security updates that tend to include fixes for a large number of vulnerabilities with risk ratings ranging from critical to low. This complicates the tracking of vulnerabilities for this OS, and the best way to ensure security is to apply the latest cumulative patch
U2.2. How to determine If You Are Vulnerable
Any default or unpatched Mac OS X installations should be presumed to be vulnerable.
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U2.4. How to Protect against Mac OS X Vulnerabilities
Be sure to stay current and have all security updates for Apple products applied by turning on the Software Update System to automatically check for software updates released by Apple. Although different schedules are possible, we recommend that you configure it to check for updates on a weekly basis at least. For more information about how to check and run the Software Update System, see the Apple Software Updates webpage -
http://www.apple.com/macosx/upgrade/softwareupdates.html
To avoid unauthorized access to your machine, turn on the built-in personal firewall. If you have authorized services running in your machine that need external access, be sure to explicitly permit them.
There are many excellent guides available for hardening Mac OS X. The CIS Benchmark for Mac OS X enumerates security configurations useful for hardening the Operating System. The actions suggested by the Level-1 benchmarks documents are unlikely to cause any interruption of service or applications and are highly recommended to be applied on the system. Also, the
Securing Mac OS X 10.4 Tiger white paper examines security features and hardening of Mac OS X.