Currently, Apple's latest firmware is iOS 11.2.1 and developers have been seeded with iOS 11.2.5. If you accidentally update or restore, you'll find yourself on iOS 11.2.1.
Iam Beer of Google's Project Zero recently released an Async_Wake exploit that works on iOS 11.1.2. Jonathan Levin, author of MacOS and iOS Internals, confirmed the exploit works on the Apple TV and is planning to upgrade his jailbreak utility iLiberTV. Levin also says he will release a jailbreak toolkit described as "a dylib for those people who end up with a send right to the kernel_task port (a.k.a tfp0) in their process, but don't know what to do next."
Following closure of the signing window, Levin said, "HA. Apple closed the 11.1.2 signing window. Told ya so. Toolkit coming soon -- for those who upgraded in time or stayed in 11.x but below 11.2. If you're on 11.2.x - that's your problem. Don't wen ETA. Next time, read carefully and heed warnings."
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