iOS 11.3 (build 15E5211a) is an official Apple over-the-air update for the iPhone 5s (Global), released on 2018-03-12T17:05:45Z. The update package is 219.75 MB. This is a delta (partial) update that requires 11.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 2d81642dc0927e38270d7b659c5e9bfd48c44ed9.zip.