iOS 12.1.2 (build 16D5024a) is an official Apple over-the-air update for the iPhone X (GSM), released on 2018-12-10T18:09:06Z. The update package is 320.97 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: c71fb29608f79d5a4d3f6b5f94b3aa0edca26659.zip.