Same problem here. Max crashes on rendering passes (could be any pass), CPU and RAM checked, its fine. Problem appears just today, i'm trying to locate it.
UPD: Ooops, my fault. Memtest86 didnt find problem in RAM, but when i did "hard" test, taking out RAM plates one by one, i found broken plate, now everything works fine. Sorry for thinking bad about Corona ))
UPD2: Still the same problem, cannot run any rendering, switched back to vray, because didnt had other choise.