iOS 11.4 (build 15F5061d) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2018-05-01T17:06:01Z. The update package is 213.36 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: 3e4b1c3d17c353b230893769e5de5221e5bde5f7.zip.