iOS 9.9.17.5.1 (build 21F90) is an official Apple over-the-air update for the iPhone XS, released on 2024-05-20T17:23:29Z. The update package is 5.66 GB. This is a delta (partial) update that requires 12.1.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: e6eedd952dac109a0a1d086a33fe6fde9698eb48.zip.