FIRMWARE DETAILS

iOS 17.2.1

Build: 21C66Dec 19, 2023Delta OTA

Stable

View details

Filename: 48b1d35932240367a387065a0c8ea9342773f4e0.zip
File size: 3.77 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: 69c5f80bfc8ff25322ef78229cd677d4ee09f81ecde4cdebeba05178984e1594
SHA-1: 4177eb7bd6429602c5064ec57c66797892801c97
Required starting builds: 20A362, 20A380, 20A392
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 iPhone11,2

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