FIRMWARE DETAILS

iOS 17.1

Build: 21B74Oct 25, 2023Delta OTA

Release CandidateStable

View details

Filename: 19946e8a049a7fe6c196af3e80f603d8697797ec.zip
File size: 4.37 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: 6b7de3863db46eda1996f09bd2cdac28b72a929125b6acd4f617437c4bec1609
SHA-1: dfd3fa4d278b269ea3e567b0351309571accb96b
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 11 Pro iPhone12,3

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