Study Finds Significant Number of Macs Running Out-of-Date Firmware Susceptible to Critical Exploits

A new research paper from Duo Security, shared by Ars Technica, reveals that a significant number of Macs are running out-of-date EFI versions, leaving them susceptible to critical pre-boot firmware exploits.

macos high sierra trio
The security firm analyzed 73,324 Macs used in production environments and found that, on average, 4.2 percent of the systems were running the incorrect EFI version relative to the model and version of macOS or OS X installed.

The percentage of incorrect EFI versions varies greatly depending on the model. The late 2015 21.5" iMac had the highest occurrence of incorrect EFI firmware, with 43 percent of systems running incorrect versions.

EFI, which stands for Extensible Firmware Interface, bridges a Mac's hardware, firmware, and operating system together to enable it to go from power-on to booting macOS. EFI operates at a lower level than both the operating system and hypervisors, providing attackers with a greater level of control.

Successful attack of a system's UEFI implementation provides an attacker with powerful capabilities in terms of stealth, persistence, and direct access to hardware, all in an OS and VMM independent manner.

Duo Security found that 47 models capable of running OS X Yosemite, OS X El Capitan, or macOS Sierra, for example, did not have an EFI security patch for the Thunderstrike exploit publicly disclosed nearly three years ago.

The research paper noted that there seems to be something interfering with the way bundled EFI updates are installed alongside macOS, while some Macs never received EFI updates whatsoever, but it doesn't know exactly why.

There seems to be something interfering with the way bundled EFI firmware updates are getting installed, leading to systems running old EFI versions. We are not able to give an exact reason why, but there are significant discrepancies between the firmware version that is actually running on real world production systems and the version that is expected to be running, given the OS build. This means that even if your Mac is still receiving security patch support, there is a non-trivial chance that your system is not running the latest version, even though you thought it was installed.

While its research paper is focused on Apple, Duo Security said the same if not worse EFI issues likely affect PCs running Windows or Linux.

In response to the research paper, Apple said it appreciates the research on the industry-wide issue and noted that macOS High Sierra automatically validates a Mac's EFI on a weekly basis to ensure it hasn't been tampered with.

We appreciate Duo's work on this industry-wide issue and noting Apple’s leading approach to this challenge. Apple continues to work diligently in the area of firmware security and we’re always exploring ways to make our systems even more secure. In order to provide a safer and more secure experience in this area, macOS High Sierra automatically validates Mac firmware weekly.

In a related blog post, Duo Security said users should check if they are running the latest version of EFI on their Macs, and it has released a tool to help do so. It also recommends updating to the latest version of macOS High Sierra.

Popular Stories

maxresdefault

Apple Releases iOS 18.4 With Priority Notifications, Ambient Music, New Emoji and More

Monday March 31, 2025 10:03 am PDT by
Apple today released iOS 18.4 and iPadOS 18.4, the fourth major updates to the iOS 18 and iPadOS 18 operating system updates that came out last year. iOS 18.4 and iPadOS 18.4 come two months after Apple released iOS 18.3 and iPadOS 18.3. Subscribe to the MacRumors YouTube channel for more videos. The new software can be downloaded on eligible iPhones and iPads over-the-air by going to...
iPhone 17 Pro 34ths Perspective

iPhone 17 Pro Launching Later This Year With These 10 New Features

Sunday March 23, 2025 10:00 am PDT by
While the iPhone 17 Pro and iPhone 17 Pro Max are not expected to launch until September, there are already plenty of rumors about the devices. Below, we recap key changes rumored for the iPhone 17 Pro models as of March 2025: Aluminum frame: iPhone 17 Pro models are rumored to have an aluminum frame, whereas the iPhone 15 Pro and iPhone 16 Pro models have a titanium frame, and the iPhone ...
top stories 2025 03 29

Top Stories: WWDC 2025 Announced, iPhone 17 Pro and iOS 19 Rumors, and More

Saturday March 29, 2025 6:00 am PDT by
Apple's big developer event is a little over two months away, and rumors about what we can expect to see in Apple's next major operating system updates are becoming increasingly frequent. A public release of iOS 18.4 is also imminent with a number of updates and improvements, although we won't be getting the major Apple Intelligence Siri upgrades that had reportedly been planned for this...
Magic Mouse Green

What to Expect From the Magic Mouse 3

Saturday March 29, 2025 10:15 am PDT by
Apple is reportedly working on a new Magic Mouse. Below, we recap what to expect. The two key rumors for the Magic Mouse 3 so far include a relocated charging port, along with a more ergonomic design. It was briefly rumored that the Magic Mouse 3 would also feature voice control, but that was misinterpreted information. Relocated Charging Port While the Magic Mouse switched from...
iOS 18

iOS 18.4 Expected Next Week - Here Are the Release Notes

Friday March 28, 2025 2:01 pm PDT by
With the second release candidate of iOS 18.4 that Apple seeded out today, the company finally provided us with release notes that give a full rundown on what to expect. There's an Apple Vision Pro app, new Apple Intelligence features for notifications and additional language support, plus an Apple News Food feature for Apple News+ subscribers, and several updates that should improve the...
Foldable iPhone 2023 Feature Homescreen

Six Things to Know About Apple's Upcoming Foldable iPhone

Friday March 28, 2025 3:54 pm PDT by
We've been hearing rumors about a foldable iPhone for almost a decade now, but it looks like we might finally see the device come to fruition in 2026. We're going to be waiting many more months for the foldable iPhone, but so far we're hearing good things. Apple wants to make it creaseless. It's taken Apple multiple years to design a foldable iPhone that it's satisfied with because Apple ...
iOS 19 visionOS UI Elements

Apple Codename Provides Clue About iOS 19's Rumored New Design

Sunday March 30, 2025 6:40 am PDT by
Multiple sources have claimed that iOS 19 will introduce a new design with more translucent buttons, menus, notification banners, and more, and there is now another clue that points towards this glass-like appearance. Bloomberg's Mark Gurman today said the new design project is codenamed "Solarium" internally. A solarium is a room with glass walls that allow in plenty of sunlight, so this...
iOS 19 Mock WWDC25 Feature

iOS 19 Expected to Run on These iPhones

Monday March 31, 2025 5:28 pm PDT by
iOS 19 will not be available on the iPhone XR, iPhone XS, or the iPhone XS Max, according a private account on social media site X that has accurately provided information on device compatibility in the past. The iPhone XR, iPhone XS, and iPhone XS Max all have an A12 Bionic chip, so it looks like iOS 19 will discontinue support for that chip. All other iPhones that run iOS 18 are expected...

Top Rated Comments

rpmurray Avatar
98 months ago
In response to the research paper, Apple said it appreciates the research on the industry-wide issue and noted that ONLY macOS High Sierra automatically validates a Mac's EFI ('https://www.macrumors.com/2017/09/25/macos-high-sierra-weekly-efi-security-check/') on a weekly basis to ensure it hasn't been tampered with. Anyone running Macs with an earlier OS (like Sierra or the ancient El Capitan) or a Mac that can't be updated to run High Sierra are SOL.
Score: 10 Votes (Like | Disagree)
840quadra Avatar
98 months ago
4.2% huh, I imagine most of those are in fact Hackintoshes, which are modified EFI to begin with.... I wonder what percent it would be if those were excluded?
I am not sure how many Hackintoshes are in production environments though. It appears that they did this study directly, not using web metrics.

I am sure there are some hackintosh computers being used commercially, though I would expect they would be excluded from such a study. Nevermind completely illegal, exposing those companies to potentially serious lawsuits.
Score: 8 Votes (Like | Disagree)
chrfr Avatar
98 months ago
4.2% huh, I imagine most of those are in fact Hackintoshes, which are modified EFI to begin with.... I wonder what percent it would be if those were excluded?
If you read through the paper, you'll see that these are not Hackintoshes. The guys who wrote this paper are well aware of the details.
[doublepost=1506697970][/doublepost]
This is an old research. I just found out that even when you have the most up to date firmware you still doomed. :D
No, this isn't old.
Score: 8 Votes (Like | Disagree)
jayducharme Avatar
98 months ago
Buy a Mac they said...

Macs can’t get viruses they said...
Well, technically they still can't, not in the way PCs do. But they're still a computer susceptible to hacking.

This discovery gives yet another good reason for always updating your Mac to the latest OS (if your hardware supports it, obviously). Sometimes Apple patches problems before we even know they exist.
Score: 8 Votes (Like | Disagree)
triptolemus Avatar
98 months ago
Can someone explain to me why it's a good idea to download a tool that interacts with the EFI firmware from a third party off of something called Github?
Score: 8 Votes (Like | Disagree)
sos47 Avatar
98 months ago
it hurts me. update to High Sierra not possible. iMac 2011
Score: 6 Votes (Like | Disagree)