About the security content of iOS 15.8.4 and iPadOS 15.8.4

Along with a bunch of fixes[0] to other OSs, Apple just pushed fixes for iOS 15.8.4 and iPadOS 15.8.4, which is available on "iPhone 6s (all models), iPhone 7 (all models), iPhone SE (1st generation), iPad Air 2, iPad mini (4th generation), and iPod touch (7th generation)".

The oldest of these ( iPad Air 2 ) was released in Oct 2014, more than a decade ago. The 6s was released in Sep 2015.

These are however just fixes for actively exploited vulnerabilities, something that Apple has done before (such as iOS 12.5.6 in Aug 2022 for iPhone 5S to patch CVE-2022-32893). The corresponding CVE list for iOS 18.4 is much longer https://support.apple.com/en-us/122371 and Apple doesn't disclose how much of these vulnerabilities exist in older versions.

[0]: https://infosec.exchange/@applsec/114258288922569866