iOS 11.4 (build 15F5071a) is an official Apple over-the-air update for the iPhone 5s (Global), released on 2018-05-07T17:11:39Z. The update package is 248.78 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: cd709044d3dc19e0cc1858d4533bba2817775c94.zip.