FIRMWARE DETAILS

iOS 17.1.1

Build: 21B91Nov 8, 2023Delta OTA

Stable

View details

Filename: 55d96e787c072c89a28a4ad5b257bf281eec9f62.zip
File size: 4.91 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: d88591120f37127bcb8c2faee9c138f2052dfc6ced64102123261ef44b9af42c
SHA-1: bea6bb1014277f4436c785b7941b771eee90873d
Required starting builds: 18G69, 18G82, 18H107, 18H17
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 Max iPhone11,6

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