[Drew68]

A problem with Ashley Madison was that valid emails accounts weren't required to sign up. You could sign up with a fake email account --or someone else's email account.

I have no doubt there are email accounts in this hack linked to people who have never heard of, much less visited Ashley Madison.

[nascarnation]

Didn’t AM send out a message to the email account requiring a web link click to verify? It seems like every internet message board I’m on does that to try and avoid spammers.

[E. Pluribus Unum]

I believe they got credit card information, too.

Can't spoof that.