FIRMWARE DETAILS

iOS 17.1.1

Build: 21B91Nov 8, 2023Delta OTA

Stable

View details

Filename: 2831cbc449b702e4b93e0a7b00478c1da95814c1.zip
File size: 3.66 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: 28f211c1d981f0212130b15df58ff25bbfbd9048745bde8a8c87e8bfa09415ff
SHA-1: 5d5cbebbfb257e0d49e23f1aab8f222fa99879fa
Required starting builds: 20B101, 20B110, 20B82
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 XS iPhone11,2

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%3B21B91.json ↗

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