iOS 9.9.11.2.6 (build 15D100) is an official Apple over-the-air update for the iPhone 5s (GSM), released on 2018-02-19T21:13:41Z. The update package is 1.35 GB. This is a delta (partial) update that requires 9.0.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: ba8a123127840cd01af6f44c45ba1e0d201ebcaf.zip.