Running PongoOS on iPhone 11’s A13 via Raspberry Pi: A New Jailbreak Breakthrough

Paradigm Shift recently disclosed a BootROM vulnerability named usbliter8 affecting millions of iPhone XS, iPhone 11 and other A12/A13 devices. The exploit requires a Raspberry Pi Pico 2 or similar microcontroller to bypass Apple’s signature checks and execute arbitrary code at the lowest level, the first such widespread BootROM bug since checkm8 in 2019.

1. Vulnerability Overview

usbliter8 is a new hardware bug in Apple SecureROM, the code permanently burned into the SoC that runs first when an iPhone powers on. The flaw exploits a defect in the Synopsys DesignWare USB controller: during DFU (Device Firmware Update) mode the controller mishandles certain USB setup packets, causing an out‑of‑bounds memory write. By corrupting memory the attacker gains control of SecureROM and can execute arbitrary code.

Affected devices include:

iPhone XS, iPhone XR, iPhone 11, iPhone 11 Pro, iPhone 11 Pro Max

iPhone SE (2020)

Apple Watch Series 4, Series 5, first‑generation Apple Watch SE

HomePod mini

Some iPad Pro models with A12X/A12Z

2. Attack Method

To launch a usbliter8 attack the adversary connects a specially crafted USB device (e.g., a Raspberry Pi Pico 2) to the target iPhone and sends precisely constructed USB setup packets. A standard PC or Mac cannot reach the vulnerable part of the controller, which is why the researchers chose the Pi.

The attack chain proceeds as follows:

Put the iPhone into DFU mode.

The Pico sends the crafted packets, triggering memory corruption.

The corruption yields code‑execution capability.

The attacker loads an unsigned bootloader or downgrades the device’s security level.

On A12 and S4/S5 chips the exploitation is relatively straightforward. The A13 SecureROM, however, employs Pointer Authentication Codes (PAC) to prevent redirection of code execution. Consequently, the attacker must perform multi‑stage memory damage to hijack the USB interrupt handler before PAC can be bypassed.

Once control is obtained, researchers can boot a custom pre‑boot environment such as PongoOS (commonly used in the checkra1n jailbreak ecosystem), and from there load unsigned kernels or debugging tools.

3. Relation to checkm8

usbliter8 complements the 2019‑disclosed checkm8 vulnerability. checkm8 covers devices from A5 (iPhone 4S) to A11 (iPhone X), whereas usbliter8 spans A12 to A13. Together they mean that every iPhone generation from the 4S through the 11 has at least one unpatchable BootROM flaw.

Both bugs share two key characteristics: they require physical access to the device and cannot be exploited remotely; they are hardware‑level issues that cannot be fixed by system updates; and they hold significant value for security researchers and the jailbreak community.

4. Security Impact Analysis

The vulnerability does not directly expose user data because the Secure Enclave Processor (SEP) – which stores passwords, encryption keys and biometric data – remains untouched.

However, gaining SecureROM control "opens a broader attack vector that could endanger the Secure Enclave," according to the researchers. In practice, the risk to ordinary users is limited: an attacker must have physical contact with the device and be able to place it in DFU mode, making remote phishing or malicious‑link attacks ineffective.

For digital‑forensics firms, the exploit has high commercial value because it provides low‑level access to the device.

5. Apple’s Response

Paradigm Shift reported the finding to Apple before public disclosure. Apple told SecurityWeek that the affected devices are older hardware and that all devices with A14 or newer chips, as well as any Mac, are not impacted.

Apple also emphasized that usbliter8 does not bypass data‑protection mechanisms; user information such as photos or messages cannot be accessed directly through this bug. The company noted that the underlying issue had been fixed in newer devices years before the research was published, and it thanked the researchers for the disclosure.

The only effective mitigation for affected devices is to upgrade to newer hardware.

6. Exploit Ecosystem

The security community quickly built a toolchain around usbliter8. Researchers released proof‑of‑concept code on GitHub, and open‑source contributors have begun integrating it with existing jailbreak tools.

The usbliter8ra1n project, for example, provides a complete boot chain: iBoot patch + SPTM bypass + TXM bypass + kernel‑patch finder + SSH ramdisk. This enables security researchers and jailbreak enthusiasts to achieve a fully custom boot process on vulnerable devices.

Users who continue to run iPhone 11 and are interested in security research or jailbreaking now have the necessary tooling, provided they accept that the hardware vulnerability will remain permanently present.