iOS 11.4.1 released with new USB Restricted Mode for iPhone

Apple has released the final version iOS 11.4.1 to compatible iPhone, iPad and iPod touch models. iOS 11.4.1 was in beta testing for some time and contains only minor updates and security fixes, including a USB Restricted Mode that is supposed to counter brute-force hacks from devices like GrayKey box.

What’s new in iOS 11.4.1?

Following are Apple’s release notes for iOS 11.4.1, which oddly do not mention USB Restricted Mode:

– Fixes an issue that prevented some users from viewing the last known location of their AirPods in Find My iPhone.

– Improves reliability of syncing mail, contacts and notes with Exchange accounts.

To learn about the security updates in this release, check Apple’s website.

Most of the major features were released with iOS 11.4, such as Messages in iCloud, AirPlay 2 and so on. This minor update only brings along a couple of bug fixes, including an update to how iOS handles USB accessories.  Available from either Face ID & Passcode or Touch ID & Passcode in Settings, depending on your device, this option disables USB Accessories from working with your iPhone if it has been more than an hour since you unlocked your device. This option is enabled by default for all users. If you see the toggle disables, it means that the feature is enabled. USB Restricted Mode was first introduced in iOS 12 beta, which has been in testing since WWDC 2018. Apple did not wait for the final iOS 12 release and included the feature in iOS 11.4.1 for all users.

USB Accessories iOS 12


Unfortunately, right after release, security researchers have confirmed that USB Restricted Mode can be bypassed by reseting the countdown timer. This can be done by plugging in Apple’s own accessories like the Lightning to 3.5mm jack adapter. Reseting the countdown timer allows more time for brute-force devices to do their work. It is likely that Apple will fix this issue with a minor update, or perhaps with iOS 12.

All eyes are now on iOS 12 which will be released this fall. Currently in developer and pubic beta testing, the new update includes a number of new features including improved performance for all devices, Group FaceTime video calls, Screen Time, ARKit 2, group notifications, camera effects, Memoji and much more.

iOS 11.4.1 is available to download over-the-air from Settings > General > Software Update. Alternatively, it can be downloaded by connecting your iPhone, iPad or iPod touch to iTunes. You can also download IPSW files for this update, in case you want to perform a clean install on your device using iTunes.