Last week, Apple released the iOS 26.5 stable update for iPhones, bringing encrypted RCS messaging, new Apple Maps experience and more. Now, in a bid to secure the iOS ecosystem, the Cupertino brand has officially barred iOS 26.5 users to downgrade by unassigning iOS 26.4.2.
Apple Stops Signing iOS 26.4.2 to Discourage iOS 26.5 Downgrades
Spotted by tipster @zollotech on X, Apple has now stopped signing the iOS 26.4.2 update indefinitely. When Apple "unsigns" an iOS version, it means that the company's servers will no longer provide the digital handshake required to install that specific software. It completely blocks access to it.
So, for users who have already installed the latest iOS 26.5 update, it is now practically impossible for them to install older iOS versions. There is no going back to iOS 26.4.2, even if the current iOS update takes a hit on performance and battery.
While this is indeed frustrating for those who prefer having a "rollback" safety net, it is a necessary move. Apple has historically maintained its stance to kill older versions of iOS to prevent threat actors from exploiting known flaws. Back in April 2026, Apple also unsigned iOS 26.4.1, followed by iOS 12.5.7, iOS 15.8.5, iOS 16.2, iOS 16.7.12 and iOS 18.7.3.
Such safeguards are necessary as Apple has faced a lot of challenges recently. From the infamous DarkSword attack in iOS 18 to a kernel-level exploit in iOS 15, it has become crucial for Apple to maintain its system integrity and the surest way to do so is by unsigning older iOS versions.
