Apple has patched older versions of macOS to protect against Meltdown

MacBook Pro

Apple has pushed out a patch to protect macOS users running older versions of the desktop OS from the major Meltdown flaw in Intel’s CPUs, following the original fix aimed at High Sierra (10.13).

This patch is for Sierra and El Capitan, the previous two incarnations of macOS (versions 10.12 and 10.11 respectively). As CNET spotted, Apple posted about the security updates on its support site. To get protected, check for new updates in the App Store.

Back at the start of January, Apple said it had already protected users against Meltdown in macOS High Sierra.

If you’re running a version of Apple’s desktop operating system prior to El Capitan, of course, you’re out of luck here.

There are still no known exploits levelled against Meltdown (or the other big bug, Spectre, which affects other processors, not just Intel), but the likelihood is that the bad guys out there may be close to weaponizing an exploit.

Stability woes

Of course, at the beginning of the week, Intel warned against installing ‘current versions’ of Meltdown and Spectre patches in general – following instability problems that have hit some PCs – but presumably that caveat doesn’t pertain to these patches from Apple.

How to protect against Spectre and Meltdown

Meltdown and Spectre

For the latest on how to protect yourself from Spectre and Meltdown, read our comprehensive guide.

Intel’s aforementioned warning applied to manufacturers and software developers as well as end-users, and if these fixes were problematic, you’d hope Apple wouldn’t have released them yet – plus these mitigations have already been applied to High Sierra at the start of the month, as mentioned, with no apparent issues.

Still, given Intel’s warning, some of the more cautious folks out there may still be a little reticent to go ahead and patch, and may feel that it’s prudent to wait a little longer, at least while there isn’t a known exploit being leveraged against Meltdown – which just underlines how much of a PR nightmare this thing is turning into for Intel.

Enter stage left Linus Torvalds to chuck just a little more fuel onto the fire from a Linux perspective. As Extremetech reports, he called Intel’s fixes for these bugs “complete and utter garbage”, never being one to mince his words.

According to emails he has sent, Torvalds is particularly unhappy about the Spectre fix for Linux machines, accusing it of being bloated and containing ‘redundant junk’, and also criticizing it for being optional, among other things. Not a happy bunny doesn’t quite cover it.

Darren is a freelancer writing news and features for TechRadar (and occasionally T3) across a broad range of computing topics including CPUs, GPUs, various other hardware, VPNs, antivirus and more. He has written about tech for the best part of three decades, and writes books in his spare time (his debut novel - 'I Know What You Did Last Supper' - was published by Hachette UK in 2013).