FIRMWARE DETAILS

iOS 17.2.1

Build: 21C66Dec 19, 2023Delta OTA

Stable

View details

Filename: ca88a337cefa8b6c9b3ed2d14fc4643f8ae00c5a.zip
File size: 4.50 GB
File type: Delta OTA
Download host: updates.cdn-apple.com
Link availability: Not verified
Source reports active
Last link check: Not checked
SHA-256: c7e8c71165f4c0bbd093a9da0124616e7701518b3129cae04b8408e96a2d4f15
SHA-1: a2848fab0a879f9605bef24eb212d906604a1ece
Required starting builds: 19A340, 19A344, 19A346, 19A348, 19A404
Board restrictions: Not reported

OTA packages can require an exact starting build and board. A matching hardware identifier alone is not sufficient for installation.

Compatible hardware (1)

iPhone XS Max iPhone11,6

Unknown

Signing is specific to the device and file. A signed build does not guarantee a downgrade or successful installation.

Source provenance

AppleDBhttps://api.appledb.dev/ios/iOS%3B21C66.json ↗

MIT — copyright 2022 emiyl
Last imported: Oct 19, 2026, 6:28 PM UTC
Record fingerprint: d446c7f095cdf40f999162af3ba1751c