Apple no longer signs iOS 15.7.3: restoration and update blocked
Apple has stopped signing iOS 15.7.3 at its servers. This means that it is no longer possible to install this specific version, either as an update or to restore your iPhone.
iOS 15.7.3 was released last January, alongside iOS 12.5.7, along with macOS 11.7.3 and macOS 12.6.3 on Mac. This is part of those updates that affect older devices that do not support the newer version of iOS, namely iOS 16. Apple thinks about users who still have old versions by offering them security patches.
According to Apple, iOS 15.7.3 closes five security vulnerabilities. Two related to the kernel (kernel) and the others were related to emails, the Maps application and the Screen Time function.
The only version that can be installed on devices that do not support iOS 16 is iOS 15.7.4. This version was released on March 27 to plug 16 security vulnerabilities, including one already exploited by hackers. Suffice to say that it is preferable to install this version.
At the same time, Apple is working on iOS 16.5, which is currently in beta for developers and public testers. There will also be iOS 17 which will debut on June 5 during WWDC 2023.
