In a somewhat predictable fashion, Apple closed the short-lived signing window for iOS & iPadOS 14.7 on Monday, almost one full week after unleashing iOS & iPadOS 14.7.1 upon the general public with important bug fixes and security patches for its mobile devices.
The change in signing status means that it is more challenging to downgrade the firmware on iPhones, iPod touches, or iPads to iOS or iPadOS 14.7. Albeit not impossible, the process to do so is now substantially more convoluted, as it would have necessitated saving .shsh2 blobs when the firmware was being signed and following unconventional steps to proceed with the firmware downgrade.
Apple regularly follows this schedule of signing and un-signing iPhone and iPad firmware in an effort to control the version of iOS or iPadOS that its user base installs. By blocking older firmware installations, Apple can artificially inflate new firmware adoption numbers to please investors while simultaneously ensuring that users are taking advantage of the latest and greatest features, bug fixes, and security improvements.
Firmware downgrades are mostly popular among jailbreakers who want to run easily exploitable firmware on their iPhone or iPad for the sake of using a jailbreak tool to do so, but this isn’t the only crowd that partakes in firmware downgrades. Apple sometimes introduces bugs in newer software updates in which the only remedy is sometimes to downgrade to the previous release until Apple releases a fix.
Those who recall the iOS & iPadOS 13.2 debacle which involved aggressive app backgrounding will attest to the aforementioned fact. So too will those who had Touch ID-equipped devices and an Apple Watch, as iOS 14.7 appeared to break the ability to unlock a paired Apple Watch when the user authenticated themselves with Touch ID on a supported iPhone. iOS 14.7.1 was later released to fix the latter bug, however it’s worth noting that it didn’t seem to affect Face ID users.
Since the jailbreak community is the most likely to partake in firmware downgrades, it is the most vulnerable to unsigned firmware changes. In this particular case, it appeared that a kernel-level exploit dubbed CVE-2021-30807 may hold the potential aid in the development of a jailbreak tool for up to and including iOS & iPadOS 14.7. This remains unconfirmed as of now, but we remain vigilant.
Notably, all versions of iOS & iPadOS, including iOS & iPadOS 14.7.1, can be jailbroken on A7-A11 devices via the checkra1n jailbreak tool. Checkra1n utilizes a hardware-based bootrom exploit dubbed checkm8 that can’t be patched by Apple with a mere software update.
As always, you can check to see which version(s) of iOS and iPadOS are being signed for your device via the handy IPSW.me online utility. You can also take advantage of our downloads page to snag any version of iOS or iPadOS for your particular device.
Are you update that iOS & iPadOS 14.7 aren’t being signed anymore? Be sure to let us know why or why not in the comments section down below.