iOS 11.2.1 (build 15C153) is an official Apple over-the-air update for the iPhone 5s (Global), released on 2017-12-13T18:12:07Z. The update package is 54.97 MB. This is a delta (partial) update that requires 11.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: d6892bb3d53b9b54842812eb8e4409c1bece1f92.zip.