A security researcher claims to have figured out how to break the T2 security chip on modern Intel-based Macs using a pair of exploits developed to jailbreak older phones. Apple has not commented on these claims.
What the research claims
The claim seems to be that because the T2 chip is based on the older A10 series Apple processor, it is possible to use two jailbreak tools (Checkm8 and Blackbird) to modify the behavior of T2, or even install malware to the chip.
It’s not an easy hack: Not only must an attacker have local access to the Mac, but they must connect to the target Mac using a non-standard “debugging” USB-C cable and run a version of a jailbreaking software package during startup.