Apple Offers Fix For macOS Monterey Bug Bricking Some T2 Macs

When macOS Monterey was rolled out, an issue arose whereby some Macs with T2 chips were bricking. 9to5Mac reports that this has now been resolved.

Now, Apple says it has identified an issue affecting the T2 security chip that caused this problem and is rolling out a fix to prevent it from happening in the future. In a statement, Apple explained (via Rene Ritchie): We have identified and fixed an issue with the firmware on the Apple T2 security chip that prevented a very small number of users from booting up their Mac after updating macOS. The updated firmware is now included with the existing macOS updates. Any users impacted by this issue can contact Apple Support for assistance. To prevent this problem from occurring to additional users, Apple has rolled out an updated version of the bridgeOS firmware that runs on the T2 security chip. Users already impacted by the problem are instructed to contact Apple Support for assistance.

More Details on the Mac T2 Security Chip Jailbreak

Catalin Cimpanu shares more details of the T2 chip jailbreak I wrote about last week.

The attack requires combining two other exploits that were initially designed for jailbreaking iOS devices — namely Checkm8 and Blackbird. This works because of some shared hardware and software features between T2 chips and iPhones and their underlying hardware.

Unfortunately, since this is a hardware-related issue, all T2 chips are to be considered unpatchable. The only way users can deal with the aftermath of an attack is to reinstall BridgeOS, the operating system that runs on T2 chips.

Apple’s T2 Security Chip Jailbroken by Checkra1n

The latest update of checkra1n adds support for bridgeOS, which runs on the T-series of chips. These are responsible for the Touch Bar, managing encrypted data in its Secure Element, and controlling Mac camera access.

The ability to exploit the T2 processor could also allow you to bypass the anti-repair mechanism built into the Touch Bar. Further, it may allow hackers to get rid of the password or unlock MDM-locked systems.

As far as the OS goes, we could also add secure boot certificates like Microsoft’s secure boot signing or a self-signed Linux certificate.

Digging into Apple's T2 Chip

AppleInsider has a good piece on Apple’s T2 chip. It’s incomplete in that it doesn’t cover the T2’s built-in image signal processor and SSD controller, but it’s still good info to have, and we recommend it.

If you spent any time looking into which Mac desktop or notebook to buy before you paid out for a shiny new machine, you’ll have seen Apple’s website extolling the fact that many of them have T2 security chips. That’s nice. Only, it’s more than nice, it’s more than a way to invisibly secure your Mac, it is a process that has a dramatic and visible effect on just about everything you do.

Communal Head Scratching to Help Solve Your Problems – Mac Geek Gab Podcast 758

It’s true, your two favorite geeks have come together again to have a “communal head scratch” about all the questions and problems you’ve submitted. Then it’s on to some happy tips, including one about working around the new Dropbox limitations. Download, press play, and learn at least five new things… and get your questions answered, too!