Calling this backdoor "vulnerable code" is a gross mischaracterization. This is closer to a large scale trojan horse, that does not have to be randomly discove

Calling this backdoor "vulnerable code" is a gross mischaracterization. This is closer to a large scale trojan horse, that does not have to be randomly discovered by a hacker to be exploited, but is readily available for privileged remote code execution by whoever have the private key to access this backdoor.