An iOS security researcher announced on Twitter earlier today that they have discovered a new jailbreak for iPhones (via The Verge). This new exploit — based on a bootrom vulnerability — is called “Checkm8” and could either be impossible or extremely difficult for Apple to patch.
You might not have heard the term “jailbreak” in a while. Jailbreaking is to iOS devices what bootloader unlocking is to Android devices in that it gives a user unrestricted access to fundamental aspects of the underlying hardware of a smartphone. Back in the early days of iPhones, jailbreaking was incredibly popular because of how many limitations there used to be with the devices, such as non-customizable wallpapers, no ability to install third-party apps, etc.
Jailbreaking enthusiasm has died out over the past few years due to a variety of factors. The biggest one is that Apple has added a lot of previously-forbidden features to iOS, making jailbreaking unnecessary for most users. Apple also has gotten much better at patching exploits which limits how long a jailbreak can last.
According to The Verge, though, Checkm8 is one of the biggest jailbreaking developments in years due to the sheer scope of what it covers.
Checkm8 could be the biggest development for jailbreaking enthusiasts in years.
With Checkm8, anyone with an iPhone made since the 4S all the way up to the iPhone X can use it. The jailbreak itself is based on a flaw in the boot storage of the iPhone itself, not in the software, and any iPhone with an A5 — A11 chip can use it. It appears Apple patched the flaw starting with the A12, so the iPhone XS and iPhone 11 lines cannot use it.
It’s still early days yet, so if you’re an iPhone user itching to jailbreak your device, you should get ready for a wait. As of now, the jailbreak only works in a tethered state — i.e., with the iPhone plugged into a computer — and it doesn’t last beyond a reboot of the device, making it incredibly impractical. However, in time it could become an untethered jailbreak that lasts even through a reboot, which would be a huge development for the jailbreaking community.
So far, Apple hasn’t made any comments on the news.