The system suffers from the absence of a kernel module signature verification. If an attacker can execute commands on behalf of root user (due to additional vulnerabilities), then he/she is also able to load custom kernel modules to the kernel space and execute code in the kernel context. Such a flaw can lead to taking control over the entire system. First identified on Nissan Leaf ZE1 manufactured in 2020.
https://www.nissan.co.uk/vehicles/new-vehicles/leaf.html
http://i.blackhat.com/Asia-25/Asia-25-Evdokimov-Remote-Exploitation-of-Nissan-Leaf.pdf