Older iPhones and Apple Watches, Exposed to Usbliter8 SecureROM Exploit

Key Takeaways SecureROM Targeted: Usbliter8 BootROM exploit affects iPhones and Apple Watch devices. Physical Access: The exploit chains a USB controller bug and a device firmware configuration weakness, requiring physical USB access to the target. Unpatchable Flaw: Because the code is immutable, the flaw cannot be patched via software. A new, unpatchable Apple SecureROM flaw exploit was discovered. The exploit, which was dubbed Usbliter8 by cybersec researchers. chains two flaws to trigger an out-of-bounds write, letting the attacker overwrite critical memory, escalate privileges, and execute arbitrary code with full system privileges

Cybersecurity company Paradigm Shift published a proof-of-concept (POC) code, reviving concerns about hardware-level flaws hardcoded permanently into Apple's silicon.

How the Usbliter8 Exploit Works Usbliter8 chains a USB controller bug with a device firmware configuration weakness, the report said . Conducting an attack requires physical USB access, with the attacker connecting a microcontroller board such as a Raspberry Pi Pico 2 and sending crafted USB setup packets.

A proper Setup transaction consists of two packets sent by the host | Source: Paradigm Shift The report says Apple 's signature checks are bypassed, enabling code execution at the device's lowest level before the OS loads. Affected devices are all released in 2018 and 2019:

iPhones running A12 and A13 chips (including the iPhone XS, XR, and iPhone 11), Apple Watches with S4 and S5 chips. Apple's Secure Enclave Processor (SEP), which protects user data, is not directly compromised. However, Paradigm Shift noted the exploit opens up wider attack vectors to compromise the Secure Enclave.

Mitigation and Apple's Response Because SecureROM is immutable, the vulnerability cannot be fixed with a software update, so migrating to newer hardware is the most effective mitigation.

Apple confirmed that iPhone, iPad, and Watch devices with A14/S6 or newer chips and Macs are not affected and that user data cannot be directly accessed via the exploit, which does not bypass data protection mechanisms.

While Paradigm Shift reported its findings to Apple before public disclosure, the company noted that the vulnerability had been fixed years earlier in its newer devices.

In April, Apple released fixes for a bug exposing deleted chat messages via logged notifications and the DarkSword iOS exploit . In March, a newer version of the DarkSword iPhone spyware exploit kit leaked on GitHub, and the Coruna iPhone hacking tool began to be used widely by cybercriminals.

Usbliter8 Exploit Targets Apple SecureROM in Older iPhones, iPhone XS–11

How the Usbliter8 Exploit Works

Mitigation and Apple's Response