Can't see a mention of this here. Basically, Apple released 10.13.1 and forgot to set a root password, or something :twitch:
Confirmed with one guy here who updated. Fix is to apply updates now, but other fix was to set a root password.
http://www.bbc.com/news/technology-42161823
:caine:
Yeah, this is a Windows 95 kind of bad. Fortunately, you have to have physical access to the device to exploit.
I tried to exploit over the network via ssh and I wasn't able to log in as root. I'm not sure if the guy had already done the fix or whether root login is disabled.
But free public wifi would not be good if root login is allowed over ssh.