iSuns9/libimg4_patcher

a patcher for making downgradable iOS 15 firmware

libimg4_patcher

A tool for patching a 64-bit libimg4.dylib binary to allow for improperly signed img4 images to be accepted during a restore

Build

make

Usage

1. Extract binary from an iOS ramdisk (macOS only):

   • img4 -i <ramdisk> -o ramdisk.dmg
     • img4 can be found here
   • hdiutil attach ramdisk.dmg -mountpoint ramdisk
   • cp ramdisk/usr/lib/libimg4.dylib
   • hdiutil detach ramdisk

2. Run libimg4_patcher:

   • libimg4_patcher libimg4.dylib libimg4.patched

3. Resign patched libimg4 binary

   • ldid -S libimg4.patched