iOS 11.0.3 (build 15A432) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2017-10-11T17:06:58Z. The update package is 264 MB. This is a delta (partial) update that requires 11.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 105050db9f771708cf4bd66e5ab0738e6f9b10cd.zip.