FIRMWARE DETAILS

iOS 17.5.1

Build: 21F90May 20, 2024Delta OTA

Stable

View details

Filename: 0743610d6909ab4ea33b25b5ebf054213be38c55.zip
File size: 3.88 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: 0a71543c8230c35559ec9f4385ef34f8719c4ecd47764dbd8aa5066d8f6174c6
SHA-1: 58af47abf2eae3afb29c1a6edf406a59439a70dc
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 11 iPhone12,1

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