Comment by mjevans
5 hours ago
It doesn't confer much since it COULD be only NAT and no firewall.
It's INCREDIBLY unlikely to find a case of that in the wild, but possible.
A common example of a host that might have such an address but lacks that sort of security is anything as the default route for inbound packets, E.G. like you'd want your _own_ router / firewall rather than the ISP's modem.
I've managed networks where a publicly-routable block was NATed behind their router