FIRMWARE DETAILS

iOS 26.5.1

Build: 23F81Jun 1, 2026Delta OTA

Stable

View details

Filename: fe21b602f8340454a2347960abce6725c15c2d4cb8bde1f2ed639de86dc0a86e.aea
File size: 402.7 MB
File type: Delta OTA
Download host: updates.cdn-apple.com
Link availability: Not verified
Source reports active
Last link check: Not checked
SHA-256: 0a6f88ac48408493ad2f8e55f5864e7921184f7721a93d9e5e70b09d290d2c36
SHA-1: ec3a91c58e5ed4c18f9c4a78f0ab31fe209b795f
Required starting builds: 23F75, 23F77
Board restrictions: Not reported

OTA packages can require an exact starting build and board. A matching hardware identifier alone is not sufficient for installation.

iPhone Air iPhone18,4

Unknown

Signing is specific to the device and file. A signed build does not guarantee a downgrade or successful installation.

MIT — copyright 2022 emiyl
Last imported: Oct 19, 2026, 6:25 PM UTC
Record fingerprint: 5c942573abf0119b4e5bd563e9638914