FIRMWARE DETAILS

iOS 17.5.1

Build: 21F90May 20, 2024Delta OTA

Stable

View details

Filename: d7fe87a8606d19f3dfbf1ce1652dab06a5893104.zip
File size: 4.60 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: 56608c0a9887393e19c0cfb15bad39b876803dd8f08f4f4f3b8dd4545b81666d
SHA-1: 9030f9d1f60d26ee33fad60fe2fdf561da1a2783
Required starting builds: 19F77, 19G71, 19G82
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%3B21F90.json ↗

MIT — copyright 2022 emiyl
Last imported: Oct 19, 2026, 6:28 PM UTC
Record fingerprint: 1ae039bd01274135bfccfb7ce06a0234