Comment by aseipp

Subverting the secure boot/upgrade chain would require a SecureROM exploit and presumably a compromise of the Secure Enclave, so the answer is almost certainly "no" (even prior major exploits from recent memory like usbliter8 are tethered and don't exploit the enclave; the last true untethered Jailbreak was iOS 9 or something.) An upgrade would fix it. The internet reporting claims this break they are showing in this video is untethered though, which is extremely rare on its own.