Overview
- Paradigm Shift published a working proof-of-concept on June 18, 2026, showing an exploit called usbliter8 that achieves code execution inside the immutable SecureROM on A12 and A13 chips.
- The root cause is a hardware bug in the Synopsys DesignWare DWC2 USB controller that, combined with Apple’s DART configuration on those chips, lets crafted USB transfers underflow a DMA pointer and overwrite SecureROM SRAM.
- Exploitation requires physical access, forcing a device into DFU mode and attaching a cheap microcontroller (for example an RP2350/Pico-class board) to send crafted USB setup packets; the attack is not remotely exploitable.
- Affected silicon includes A12, A13, S4 and S5 families, covering iPhone XS/XR/11-era phones, certain iPads, Apple Watch Series 4/5 and HomePod mini, and the flaw cannot be patched by software so replacement or upgrades to A14+ are the main fixes.
- The public disclosure echoes the 2019 checkm8 precedent by enabling long-lived jailbreak and forensic tools, it does not show direct compromise of the Secure Enclave but increases risk for seized or unattended devices and shifts defense to strict custody and USB policies.