It's also normal for AIs to write code, and humans will merge it without reading or understanding the code. There's an "AI spaghetti" coding style, with lots of repeated code and extra code. I.e., a human will refactor duplicate code to a function. The AI sees nothing wrong with the exact same code duplicated in 10 places.

If the AIs are writing code, and they put in backdoors, eventually they wouldn't even need root access or passwords. They even now have ways for AIs to communicate, things like moltbook. The AIs could eventually figure out how to use coded messages to communicate.