Same host or different? How can you tell "over the wire"?

[Ronald F. Guilmette]

In message <4ce048ad-873e-795e-aae0-8d795d9bb85c at kicp.uchicago.edu>, 
Valeri Galtsev <galtsev at kicp.uchicago.edu> wrote:

>If A and A' do resolve beyond their SOA for clients outside of their 
>domain. That was vulnerable for abuse, and hardly anybody does that 
>these days. Am I missing something?

As I understand it, sadly, there are still a couple of zillion open
recursive resolvers out there.

I would anticipate that Bad Actors are neither more likely nor less
likely than the general poulation to put such an abomination online.