Download iOS 15.2.1 (19C63) for iPhone 11 Pro Max

You will have to note that you can only restore signed IPSW firmware files using iTunes or 3utools.

❌ This IPSW firmware is not being Signed by Apple

Firmware Identifier iPhone12,5
iOS Version 15.2.1
Release Date 2022-01-12
Update Date 2024-06-03
Sha1sum
3587cb3ea166d0cd106a4c64c1759886d488d220
Sha256sum
47e421ed716d3e18b1a43f03b703988c7952319622bc344f3ca70ec922b57b00
md5sum
644301f384b251f8897668bb29dc4614
Size 7.01 GB
FileName
iPhone11,2,iPhone11,4,iPhone11,6,iPhone12,3,iPhone12,5_15.2.1_19C63_Restore.ipsw
Status

Download IPSW (7.01GB) Check device info
Release Notes

It should be noted that these are the official release notes for the from Apple

iOS 15.2.1 contains bug fixes for your iPhone including:

For information on the security content of Apple software updates, please visit this website:

https://support.apple.com/kb/HT201222