iOS 12.1.1 (build 16C5050a) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2018-11-15T18:04:55Z. The update package is 65.18 MB. This is a delta (partial) update that requires 12.1.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 114099ad631458aa3c2a2a5ec9b50f42ea097011.zip.