Jailbreaking iOS 11.1.2 – An adventure into the XNU kernel.
You can download it from the following link: https://packetstormsecurity.com/files/download/146221/jailbreaking-ios-11.1.2-an-adventure-into-the-xnu-kernel.pdf
Source: https://packetstormsecurity.com/files/146221/Jailbreaking-iOS-11.1.2-An-Adventure-Into-The-XNU-Kernel.html