iOS 9.9.11.1 (build 15B93) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2017-10-23T17:06:11Z. The update package is 1.58 GB. This is a delta (partial) update that requires 8.1.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 300f748a8ed9706cb2590908f450047a3c0587ec.zip.