Apple no longer signing iOS 15.2.1, thwarting downgrades from iOS 15.3

After releasing iOS & iPadOS 15.3 to the general public last week with important bug fixes and improvements for iPhone and iPad users alike, the Cupertino-based company has just this evening closed the signing window for the predecessor iOS & iPadOS 15.2.1 firmware.

Downgrade iOS 15

When Apple stops signing a certain version of iOS or iPadOS, this effectively means that the company has reconfigured its servers to deny requests to downgrade or restore to that particular version. As a result, Finder (on macOS) or iTunes (on Windows) will throw an error message when users attempt to do this.

While most iPhone and iPad users excitedly download and install the latest software updates on day one, that isn’t the case for everyone; especially jailbreakers. Consequently, it is jailbreakers who are the most likely to downgrade or restore to older firmware, as those versions tend to be vulnerable to exploits used by jailbreak tools.

Given the more than decade-long cat-and-mouse game between Apple and the jailbreak community, it’s no wonder that Apple tries so hard to keep users from being able to downgrade or restore to jailbreakable versions of iOS or iPadOS.

However, it’s important to note that even non-jailbreakers sometimes find the urge to install older version(s) of iOS or iPadOS, especially when an update introduces bugs that break something that user would otherwise find valuable. For example, iOS 14.7 broke the ability to unlock paired Apple Watches with an iPhone’s Touch ID authentication, while iOS & iPadOS 13.2 imposed overly-aggressive app backgrounding management.

Blocking prospective jailbreakers from carrying out their hopes and dreams isn’t the only thing Apple has to gain from blocking installations and restorations to older firmware; doing so also lets the company gloat to shareholders about new firmware adoption during Keynote presentations. In addition to that, Apple gets to corral users underneath the protective umbrella of security patches.

Love it or hate it, it seems Apple’s firmware un-signing shenanigans are here to stay, but that’s why we always recommend that prospective jailbreakers always stay on the lowest possible firmware and avoid updates at all costs. Doing so helps ensure your jailbreak eligibility when an exploit comes out for the firmware you might be using.

As always, you can check to see what version(s) of iOS or iPadOS are being signed for your device on the handy website. You may also download any iPhone or iPad firmware file you might need from our dedicated Downloads page.

Are you sad to see that iOS & iPadOS 15.2.1 are no longer being signed by Apple? Discuss in the comments section down below.