iOS 8.1.2 (build 12B440) is an official Apple over-the-air update for the iPhone 5 (GSM), released on 2014-12-09T17:49:04Z. The update package is 956.14 MB. This is a delta (partial) update that requires 7.1.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 3f1f6db9c7001ad9621fd316b90f76dcc64471fe.zip.