FIRMWARE DETAILS

iOS 17.1.1

Build: 21B91Nov 8, 2023Delta OTA

Stable

View details

Filename: 6d10e1be4fa18e2051761b1b26c6d316e5c51586.zip
File size: 3.63 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: 53ea97e463d48005a0a14e9cf2a8ada9dc99d8886d567d27c3fe26c93d289537
SHA-1: 8e9508a658a88a405ec10d4d09964cf81a5ca958
Required starting builds: 20C65, 20D47, 20D67
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%3B21B91.json ↗

MIT — copyright 2022 emiyl
Last imported: Oct 19, 2026, 6:28 PM UTC
Record fingerprint: 920b0a70bb6d0ccadee92018f5db3f40