In case those of you still using Yosemite might have missed or overlooked it, Apple released a security update this morning (January 17, 2017) which also fixes a kernel issue that sometimes makes the system to become unresponsive. The update is available through the App Store and the installation requires a restart.

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that sounds like a familiar problem here. Will have to get that, thanks for the heads-up.

There's a similar El Cap update.

Interesting. I didn’t find anything on the App Store other than a GarageBand updater. Some further digging didn’t show anything either beyond the El Cap Security Update 2016-003 Supplemental Update Artie referred to. What’s up?

You may have had a silent update as mentioned in 'Fruitfly' malware patched by Apple relies on 'ancient' Mac system calls

That’s always a possibility, however unlikely it may be in cases like this where non-security OS issues are addressed. I’d like to know for sure though, as there’s no indication in App Store of any recent OS updates on the Mac in question, and I also don’t know if the update changed the OS build number. I wonder where joemikeb got his info, and if there's more detail where that came from.

I found out about the update from an App Store Notification and is essentially a quote of the upgrade note on the App Store. I had just finished updating my Mac mini server when MacRumors posted their article. (NOTE: the MacRumors article has been expanded since I first read it. The initial article had almost no detail and did not mention the Mavericks update.)

Uhhh... The date on your linked article is Thursday September 1, 2016.

Edit: A re-release of the original El Cap update and the supplemental are listed here, but there's nothing for Yosemite.