Apple Stops Signing iOS 26.5 and 26.5.1 Versions
Apple has ceased the digital signing of its iOS 26.5 and 26.5.1 software versions. Users who have updated to the latest release can no longer downgrade to these earlier iterations.
Apple's iPhone devices will no longer accept older versions of iOS 26.5 and 26.5.1.
Tech giant Apple has officially concluded the digital signing process for the iOS 26.5 and iOS 26.5.1 operating system versions. This decision means that iPhone users who have upgraded to the most recent release, iOS 26.5.2, will be unable to revert to the previous iterations.
This action aligns with Apple's standard procedure, which typically involves stopping the signing of older software versions approximately one week after a new stable release becomes available. The timeline for iOS 26.5.1, released on June 2, 2026, and iOS 26.5.2, released on June 29, 2026, follows this pattern.
Ending the signing window for older iOS versions is a security measure implemented by Apple. The company aims to prevent users from installing outdated software that might contain vulnerabilities, thereby enhancing overall device security.
For context, the iOS 26.5.1 update addressed a specific issue where certain iPhone Air and iPhone 17 models might experience difficulties with wired charging when the battery was critically low. The subsequent iOS 26.5.2 release primarily focused on delivering essential security fixes.