FIRMWARE DETAILS

iOS 17.1.1

Build: 21B91Nov 8, 2023Delta OTA

Stable

View details

Filename: 17d10a943085a03a2403dbc75ab68f97dc58917f.zip
File size: 3.69 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: 23592efa76a3525df5a4c1cf83623bc5f937437895539300be8da70f16c36c9a
SHA-1: ad43f77bc814be63b9b1658c6af653e57d1a93d8
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 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