Apple has today released a supplemental update for OS X El Capitan. This is an update that addresses some minor security issues discovered within Apple’s past operating system. According to the release notes for security update 2016-003, there is a kernel fix where Macs could freeze up and become unresponsive. This update was released with the last update, how it was re-released today after some issues were found with the update.
Users of OS X El Capitan can go to the Mac App Store and find it under the software updates page. This ins’t a big update so it shouldn’t take too long for the update to download. A restart will be required for these changes to take effect.