FIRMWARE DETAILS

iOS 17.3.1

Build: 21D61Feb 8, 2024Delta OTA

Stable

View details

Filename: b68a63883ec23d7505b10981e89b15a8d56d1fe8.zip
File size: 3.88 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: 6712d92c0f4e0cc8875f48698899255eb93f9b4f713cdba50226ade397ef19f7
SHA-1: c3a286f36355353cd7c0cbad8ad5bc8dc0ef53be
Required starting builds: 20G75, 20G81, 20H19, 20H30
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 13 iPhone14,5

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%3B21D61.json ↗

MIT — copyright 2022 emiyl
Last imported: Oct 19, 2026, 6:28 PM UTC
Record fingerprint: caa4c3b8f1108221a1cf4826799a13ca