FIRMWARE DETAILS

iOS 17.1

Build: 21B74Oct 25, 2023Delta OTA

Release CandidateStable

View details

Filename: a01eb51e99f3cf0f9d93145d5d302924faa2a8e0.zip
File size: 3.92 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: cc3f2b6a070620afcbd6385de034286546587d0573886ff359739e2714cc4cc7
SHA-1: 18305338c643e9dfcfdf5c8777b4e8d0cd203e54
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 12 iPhone13,2

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%3B21B74.json ↗

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