Modify Ipsw File Page
Modifying an IPSW is a powerful technique that offers a glimpse behind the curtain of iOS. It allows for the removal of bloatware, the preservation of older iOS versions, and the execution of custom code. However, as Apple hardens its hardware security with every new chip generation, the era of "drag and drop" IPSW modification is fading, replaced by on-device kernel patching and runtime modification.
If you are experimenting, stick to older, exploitable devices (like an iPhone 7 or iPhone X) to learn the ropes without risking your daily driver.
Re-zip the contents (do not compress the entire folder, just the files inside it): modify ipsw file
cd ipsw_extracted
zip -r ../Custom_firmware.ipsw *
Change the extension back: mv Custom_firmware.zip Custom_firmware.ipsw
An IPSW file is essentially a tarball archive (.tar.gz file) that contains several key components: Modifying an IPSW is a powerful technique that
Given the near-impossibility of flashing a modified IPSW to an A12+ device (iPhone XR, 11, 12, 13, 14, 15, 16), the community has shifted to runtime modification. You don't modify the file on disk; you modify the kernel's memory after boot (jailbreak).
| Old Method (IPSW Modification) | New Method (Jailbreak) |
| :--- | :--- |
| Permanently deletes Setup.app | Hooks setup daemon in RAM to skip activation |
| Replaces system fonts permanently | Uses bypass Cydia tweak to remap font paths |
| Requires re-flashing entire OS | Wipes clean after hard reboot |
| High brick risk | Low brick risk (Safe Mode) | Change the extension back: mv Custom_firmware
Tool Equivalents: