Older iPhones have an unfixable security flaw – why it can’t be patched and the models affected

Here’s how to tell if your device is at risk and what to do about it.

Follow ZDNET: Add us as a preferred source on Google. Do you still use an iPhone 11, XS, XR, or SE? If so, I have some bad news. Yep, another security flaw has been discovered, and Apple can't fix this with one of its typical updates. In a blog post published on Thursday, cybersecurity firm Paradigm Shift revealed a security vulnerability that it discovered and successfully exploited in older model iPhones with Apple's A12 or A13 chip. Dubbed usbliter8, the flaw affects the boot ROM, aka SecureROM, code of an iPhone, which executes before the operating system loads. By exploiting usbliter8, an attacker could install their own malicious code or run unauthorized commands on a victimized iPhone. Also: Prime Day 2026: Live updates on Garmin, Lenovo, Apple and other tech deals Because the flaw is in the device's ROM, Apple can't patch it via a software update. The only saving grace is that the flaw can't be triggered remotely. An attacker would need physical access to your phone. They would also need enough time to restart your device and enough know-how to take advantage of the exploit. Plus, the researchers at Paradigm Shift were unable to bypass Apple's other security safeguards, such as Data Protection. As such, your files, photos, messages, and other user data are not affected by the flaw. But that doesn't mean there's no cause for concern. "BootROM vulnerabilities are relatively rare, and when they surface the physical access requirement tends to give organizations a false sense of comfort," Shane Barney, chief information security officer of Keeper Security, told ZDNET.