Intel Memory Access Design Flaw Already Addressed by Apple in macOS 10.13.2

A serious design flaw and security vulnerability discovered in Intel CPUs has reportedly already been partially addressed by Apple in the recent macOS 10.13.2 update, which was released to the public on December 6.

12 inch macbook macbook pro duo
According to developer Alex Ionescu, Apple introduced a fix in macOS 10.13.2, with additional tweaks set to be introduced in macOS 10.13.3, currently in beta testing. AppleInsider also says that it has heard from "multiple sources within Apple" that updates made in macOS 10.13.2 have mitigated "most" security concerns associated with the KPTI vulnerability.

Publicized yesterday, the design flaw in Intel chips allows normal user programs to see some of the contents of the protected kernel memory, potentially giving hackers and malicious programs access to sensitive information like passwords, login keys, and more.

Full details on the vulnerability continue to be unavailable and under embargo, so it's not yet clear just how serious it is, but fixing it involves isolating the kernel's memory from user processes using Kernel Page Table Isolation at the OS level. Implementing Kernel Page Table Isolation could cause a performance hit on some machines.

According to The Register, which first shared details on the vulnerability, Windows and Linux machines will see a 5 to 30 percent slowdown once a fix is in place. It appears Macs may not be hit as heavily, as no noticeable performance slowdowns have been reported since the launch of macOS 10.13.2.

Ionescu also says that performance drop on a system with PCID (Process-Context Identifiers), available on most modern Macs, is "minimal," so most users may not see an impact on day-to-day Mac usage.

Popular Stories

Beyond iPhone 13 Better Blue Face ID Single Camera Hole

10 Reasons to Wait for Next Year's iPhone 17

Friday September 13, 2024 2:40 am PDT by
Apple's iPhone development roadmap runs several years into the future and the company is continually working with suppliers on several successive iPhone models simultaneously, which is why we sometimes get rumored feature leaks so far ahead of launch. The iPhone 17 series is no different – already we have some idea of what to expect from Apple's 2025 smartphone lineup. If you plan to skip...
Generic iOS 18 Feature Real Mock

Apple Shares Full List of Over 250 New Features and Changes Coming With iOS 18

Wednesday September 11, 2024 7:16 am PDT by
Following its iPhone 16 event on Monday, Apple shared a PDF on its website with a list of all new features and changes coming with iOS 18. The list includes many features that were already announced, including Apple Intelligence, new customization options for the Home Screen and Control Center, a redesigned Photos app, several enhancements to the Messages app, a Passwords app, and more....
iphone 16 pro models 1

Skipping the iPhone 16 Pro? Here's What's Rumored for iPhone 17 Pro

Wednesday September 11, 2024 8:20 am PDT by
Will you be skipping the iPhone 16 Pro and waiting another year to upgrade? If so, we already have some iPhone 17 Pro rumors for you. Below, we recap key new features rumored for the iPhone 17 Pro models so far: 24MP front camera for all iPhone 17 models: All four iPhone 17 models will feature an upgraded 24-megapixel front-facing camera, according to Apple supply chain analysts Ming-Chi...
iphone 16 pro colors 1

Here's When iPhone 16 Pre-Orders Begin in Every Time Zone

Thursday September 12, 2024 6:12 am PDT by
Pre-orders for the iPhone 16, ‌iPhone 16‌ Plus, iPhone 16 Pro, and ‌iPhone 16 Pro‌ Max are set to begin on Friday, September 13 at 5:00 a.m. Pacific Time, with the new devices set to become available in multiple countries around the world simultaneously. We've compiled pre-order times for various countries to help MacRumors readers be among the first to order. This list isn't...
iphone 16 pro apple intelligence

iPhone 16 Pro and Pro Max Shipping Estimates Extending Into October

Friday September 13, 2024 5:48 am PDT by
Apple began accepting pre-orders for all four new iPhone 16 models today, and shipping estimates for the iPhone 16 Pro and Pro Max on Apple's online store in the U.S. are already beginning to slip into October for many configurations. As of 6:45 a.m. Pacific Time, the iPhone 16 Pro and Pro Max were facing a 2-4 week shipping delay for some configurations on Apple's online store, with...
iphone 16 pro apple intelligence

Apple Intelligence Features Expected to Roll Out in This Order Between iOS 18.1 and iOS 18.4

Friday September 13, 2024 1:01 pm PDT by
iOS 18 will be released to the public on Monday, but the first Apple Intelligence features will not be available until iOS 18.1 is released in October. Apple Intelligence features will continue to roll out in iOS 18.2 and beyond, with the expected roadmap outlined below per Apple's website and rumors. Apple Intelligence requires an iPhone 15 Pro model or any iPhone 16 model, and it will...

Top Rated Comments

pier Avatar
88 months ago
What about El Capitan and Sierra?
Score: 35 Votes (Like | Disagree)
alex00100 Avatar
88 months ago
I'd still replace my battery just to be sure ;)
Score: 27 Votes (Like | Disagree)
RoobyRoobyRoo Avatar
88 months ago
Erm...no, 10.13.2 has been out for quite a bit, almost a month ago.

Might have even been in earlier beta's as well.
So quick that it happened in the past! I like this new time-bending Apple.
Score: 13 Votes (Like | Disagree)
SecuritySteve Avatar
88 months ago
Anyone know if this applies to security-patches for Sierra / El Capitan?
Score: 10 Votes (Like | Disagree)
CrashX Avatar
88 months ago
For anyone interested, using the Potts-Kant benchmarks on the latest releases of both concurrent versions of Mac OS -

We're running benchmark processes concurrently with PCID disabled, employing supplementary reservoir matching sequences throughout our lab here at Duke.

The testing has just begun - so I'll be posting the results here in about an hour, for anyone interested in how their machines might be affected.

Students have been instructed to take the machines through a variety of real world tests -

So we'll be posting that, as well as the conclusive results provided by our benchmark studies - to hopefully help clear the air and provide a more balanced issuance of the possible affections of data-protected kernel-modeling architecture implications.
Score: 9 Votes (Like | Disagree)
belvdr Avatar
88 months ago
What do we make of this really? I think someone should do a comparative test on handbrake or anything that solely uses CPU and only then we can tell the difference between 10.13.2 and any previous versions of macOS
This has nothing to do with CPU utilization. Rather, you will see a performance penalty when an applications makes system calls, such as to files or network access. Essentially it occurs when ring 3 needs to access something at the more privileged ring 0.
Score: 8 Votes (Like | Disagree)