If you use an iPhone, this is more important than ever, especially if it was made years ago. Security researchers have found a devastating, hardware-level vulnerability that leaves millions of older Apple devices exposed to a permanent jailbreak and arbitrary code execution. Dubbed ‘usbliter8,’ this newfound flaw circumvents Apple’s ironclad bootup protections, thereby exposing the devices to risk.
And the concerning bit is that it cannot be fixed with an update from Apple.
Since the vulnerability resides in code burned into the chips during manufacturing, Apple cannot fix it. No software update, security patch, or forced reboot can ever fix this vulnerability, thus keeping the door open to hack exploits.
For millions of users holding older iPhones, iPads, and Apple Watches, security now becomes a major concern.
What’s wrong with old Apple devices
Discovered by cybersecurity research firm Paradigm Shift, the ‘usbliter8’ issue targets SecureROM (also known as BootROM) — the absolute first layer of code executed the moment an Apple device powers on. SecureROM acts as the root of trust, i.e., it verifies that the operating system is authentic and signed by Apple before allowing the phone to boot.
The flaw lies within the Synopsys DWC2 USB controller utilised by Apple’s A12 Bionic, A13 Bionic, S4, and S5 systems-on-chip (SoCs). Researchers discovered they could trigger a repeatable buffer underflow during firmware updates by exploiting how the controller handles data via Direct Memory Access (DMA).
On the vulnerable A12 and A13 chips, Apple configured the chip’s internal memory management unit to run in “bypass mode.” This allows a precisely timed exploit to step backwards through the device’s SRAM, overwrite critical pointers, and hijack the boot process.
The exploit takes less than two seconds to execute. Once active, it completely steps outside Apple’s secure chain of trust, giving attackers privileged “EL1” access inside SecureROM. From there, hackers can bypass code-signature checks, demote the chip’s production mode, and boot custom, unsigned operating system images. This is what the iPhone jailbreaking community relies on, but a hacker could now pull it off on someone who isn’t interested in it.
Is your iPhone, iPad, Apple Watch affected?
Apple successfully insulated the newer processors from this mistake, beginning with the A14 chip, by correctly configuring memory protections. However, the A12 and A13 generations were left unsafe.
As a result, all the devices utilising these chips are at risk. What’s concerning is that there are millions of these devices powered by these chips out in the wild, and none of these can be fixed. Here’s a list of the Apple devices affected:
A12 chip-powered devices: iPhone XR, iPhone XS, iPhone XS Max, iPad Air (3rd Gen), iPad mini (5th Gen), and iPad (8th Gen).
A13 chip-powered devices: iPhone 11, iPhone 11 Pro, iPhone 11 Pro Max, iPhone SE (2nd Gen), and iPad (9th Gen).
Wearables and others: Apple Watch Series 4 and 5, Apple Watch SE (1st Gen), and the HomePod mini.
Despite their age, these devices continue to be out there in the wild and still in use. In fact, Apple recently announced that most of these devices will get the latest software updates announced at the WWDC 2026. The iPhone 11 generation will get the latest iOS 27 update.
How much of a risk are you at?
Don’t panic, as security experts highlight that ‘usbliter8’ is not a remote weapon. A rogue actor cannot hack your phone via a malicious website, a text message, or a compromised Wi-Fi network using this vulnerability alone. Executing the exploit requires absolute physical access to the device.
Because of these physical requirements, the practical risk to the average consumer is low. Your phone won’t be silently compromised while sitting in your pocket.
What should users of affected iPhones do?
If you own an iPhone 11, iPhone XR, XS, or an iPhone SE (2nd Generation), your device is technically vulnerable to usbliter8 for the rest of its operational life.
1. Assess your Personal Risk Profile
For the vast majority of everyday users, there is no need to throw away your phone. The exploit requires direct physical access and specialised hardware. However, if you belong to a high-risk demographic, such as investigative journalists, political activists, corporate executives handling high-value trade secrets, or government dissidents, the security calculus changes entirely.
2. Upgrade your hardware
As Paradigm Shift’s researchers bluntly noted in their technical write-up, “migrating to newer hardware remains the most effective mitigation.” Because the flaw is hardcoded into the physical architecture of the A12 and A13 chips, no future iOS patch will ever fix it. If you require absolute, state-of-the-art security against physical tampering, your best option is to upgrade to a device powered by an A14 Bionic chip or newer (iPhone 12 series and beyond). Apple’s latest phones are powered by the A19 chip.
3. Don’t share your devices
Because usbliter8 relies entirely on physical access, your phone is only as safe as the environment it is in. Never leave your device unattended in public spaces, hotel rooms, or shared workspaces where an “evil maid” attack (unauthorised physical tampering while you are away) could occur. Be exceptionally cautious when passing through border checkpoints or international travel hubs where devices may be taken out of your sight by authorities.
4. Use a complex Alphanumeric passcode
While usbliter8 grants control over the application processor’s boot chain, it has not yet been shown to directly compromise Apple’s Secure Enclave – the isolated hardware bunker that stores your cryptographic keys and biometric data. However, gaining BootROM control allows attackers to potentially disable the mechanism that limits password retry attempts.
To protect your actual data from being forced post-boot, change your lock screen password from a simple 4-digit or 6-digit PIN to a complex, long alphanumeric passcode.
5. Keep software updated
It might seem pointless to update your software in this case when the foundational chip is broken, but it is actually more important than ever. Attackers frequently “chain” exploits together, using a remote WebKit flaw to get into a phone, and then a local hardware flaw to anchor themselves permanently. Keeping your iOS software updated ensures that remote access remains as locked as possible.