iOS 11.4 (build 15F5079a) is an official Apple over-the-air update for the iPhone X (Global), released on 2018-05-17T17:02:21Z. The update package is 300.04 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: f39a6466ee9f20a9ef61e7b143f179ffadfbb8bf.zip.