Tethered jailbreaks are back

Summary: A new iPhone Boot ROM exploit called checkm8, published on GitHub by axi0mX, affects the iPhone 4S through the iPhone X and was patched in devices with A12 and A13 CPUs. The exploit gives anyone with physical control of a phone the ability to run arbitrary code at boot, and it does not yet include the code needed to boot a jailbroken kernel.
Key Takeaway: Apple still sells vulnerable hardware such as the iPhone 8, and the exploit cannot be detected on a phone that has been compromised, so jailbreak detection has to rely on identifying side-effects of the exploitation.

Read the original at Trail of Bits Blog ↗