iOS 12.5.1

Apple stops signing iOS 12.5 following the release of iOS 12.5.1

Apple regularly releases software updates for the company’s many platforms, mobile and desktop alike. Interestingly, while most Apple’s software updates target either newer devices or upgrading the user experience of the company’s latest firmware iteration, a few heads turned when Apple released iOS 12.5.1 earlier this month to address a COVID-19 exposure notification bug that purportedly affected older iPhones.

Given that a software update was released, despite being for an older iteration of iOS, it should come as no surprise to anyone that Apple would soon close the signing window for what was previously the latest version of iOS 12. This happened Tuesday evening after Apple officially made the move to stop signing iOS 12.5, the predecessor of the newer iOS 12.5.1 update.

Does the Chimera jailbreak work on the newly released iOS 12.5.1?

On Monday, we reported on Apple's point update release of iOS 12.5.1 for older devices which cannot run iOS 13 and higher. The only stated change in the update was a fix for a bug in the COVID-19 exposure notifications feature, which Apple had previously added to older firmwares to allow more device owners to make use of it.

Although the release notes didn't mention any other changes, it would not have been unusual for Apple to have taken the opportunity to patch the vulnerabilities used by iOS 12.x jailbreaks, such as the Chimera jailbreak for iOS 12-12.5. The update could also have rendered the jailbreak tool unusable accidentally. Unrelated changes in the firmware, or hard-coded firmware support in the Chimera app itself, could also have required an update to the tool for it to work again.