FIRMWARE DETAILS

iOS 17.1

Build: 21B74Oct 25, 2023Delta OTA

Release CandidateStable

View details

Filename: c529560a2c7781585c43d95b6fe5dde9d2f34fe9.zip
File size: 4.34 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: f7c3f95a17aaae7584e19e74a7fbd5ca8fd5bfa8fa45ab69ae0f362fb4f7cd12
SHA-1: 85af847ab73843f7ec79a1076a2ceccac7734e22
Required starting builds: 19B74
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%3B21B74.json ↗

MIT — copyright 2022 emiyl
Last imported: Oct 19, 2026, 6:28 PM UTC
Record fingerprint: ce1037df7218db6f4121eac6e89afc29