iOS 8.4.1 (build 12H321) is an official Apple over-the-air update for the iPhone 5 (GSM), released on 2015-08-13T18:05:13Z. The update package is 328.18 MB. This is a delta (partial) update that requires 8.2 already installed. This update is currently signed by Apple, so it can be applied from Settings › General › Software Update.

Payload file: aebe2f6926a3a77ba5af29e8e8d40d3e41298ec2.zip.