First Public macOS Kernel Exploit on Apple M5 Prepared Using Mythos Preview in Five Days

Researchers published a report on the first public macOS kernel memory corruption exploit that bypasses Apple M5’s Memory Integrity Enforcement (MIE), achieving local privilege escalation to a full root shell on macOS 26.4.1 (25E253) running on bare-metal M5 hardware. The chain was developed rapidly with assistance from Anthropic’s Mythos Preview AI; full technical details remain private pending an Apple patch, and affected systems on M5 hardware running the specified OS are at theoretical risk until remediation.