Unlike Microsoft, Apple has so far not committed to a regular patch cycle, and today's release of IOS 4.3.2 as well as the OS X Security Update 2011-002 came somewhat as a surprise. [1]

Both include security fixes that should be applied rather sooner then later. The OS X update also includes Safari 5.0.5 . We will update this diary once the Apple support page with security details is live.

The patch is pretty small compared to other Apple patches (about 4 MB). You need to restart your system after applying the security patch. I applied it to one system with PGP full disk encryption, and so far no ill effects. 

[1] http://support.apple.com/kb/DL1376

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Johannes B. Ullrich, Ph.D.
SANS Technology Institute
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