FIRMWARE DETAILS

iOS 17.5.1

Build: 21F90May 20, 2024Delta OTA

Stable

View details

Filename: 92726f579e1285ca8260cadc45f8a10584ef6072.zip
File size: 4.76 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: f97d548cb7b6f33a50ec655af1dd3a3207c2c14429569c177d31bfbbb9922f1d
SHA-1: 3e73022fe9056f686bd183a29ab274affa3f9b6a
Required starting builds: 19C56, 19C57, 19C63
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 13 iPhone14,5

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