Apple stopped signing iOS 26.4.2, meaning iPhone users who updated to iOS 26.5 can no longer roll back to the previous version.
Whenever Apple rolls out an iOS update, it allows users to go back to the previous version if they run into bugs or other issues. But once the company considers the new release stable, it stops signing the older build.
What does ‘signing’ iOS versions actually mean?
When Apple signs any version of iOS, it gives that software a stamp of approval that an iPhone checks before installing anything. If that signature is missing, your iPhone won’t even accept the file, even when connected to a Mac or PC.
Apple’s signing system isn’t only about stability, though. It also serves as a security mechanism that prevents users from going back to an older version with known vulnerabilities. It’s an intentional decision that allows Apple to keep iPhones on the latest and most secure version of iOS.
Apple stopped signing iOS 26.4.2 earlier this week, as spotted by Aaron Zollo on X. So, if you were hoping to downgrade to iOS 26.4.2 for some reason, that ship has sailed.
iOS 26.5 might be the last update before WWDC26
This shouldn’t be a big deal, as iOS 26.5 has been a smooth release by most accounts. The update comes late in Apple’s annual software cycle and seems solid.
It isn’t a big update, but it does include a handful of solid additions, like 11 new Pride wallpapers, smarter place suggestions in Apple Maps, and a new yearly subscription payment option for apps.
It also brings end-to-end encrypted RCS messaging, but that feature remains in beta and only works with certain cellular providers.
With only a few weeks left for WWDC26, iOS 26.5 will likely be the last iPhone update before Apple unveils iOS 27.
Anurag Chawake is a tech-focused writer specializing in smartphones, apps and consumer technology. His interest in computers began during the Windows 98 era, eventually leading him to explore everything from operating systems to mobile devices and PC hardware. Anurag previously contributed to The Indian Express, covering Apple, Android, gaming and the broader technology landscape.
