iOS 11.4.1 (build 15G77) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2018-07-09T17:09:33Z. The update package is 248.61 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: 86bcf7b266d70c4adcec08de991093c43310d7fb.zip.