In Alaska we have General Communications, Inc. as one of our main providers. Several times this year I've gotten something of the sort that you refer to, although they asked only for my current email address and password (of all things!). It is sent under the correct gci.net url.

I have not responded to the email, of course, but after the second time I called GCI and asked if by chance it was theirs. They said No, that they were aware of it and wree trying to track it so they could shut it down.