Many of my clients have been spammed by La Capitana Real Estate lately. And I mean many. Hundreds.
However, they seem to have found a way to spam that works. And that sucks.
They have created a Google Group, added all their victims there, and let google do the dirty work.
What's the problem?
Google group mails are not blockable at SMTP-level because their senders contain a sort of hash and the recipient address, and no group name. That's incredibly stupid in google's part.
The messages they send are huge (6MB and up) so spamassassin can not process them. The SA docs say this will not happen because of "the economics of spam". Well, it happens when you make google do it!
I don't want to go back to the old days of keeping a local queue-level address blacklist. That's awful!
I have complained to google, I have complained to the spammers, even by phone. They use the standard defense of "we are just inviting people". "They can unsubscribe if they want to". "This is not spam"
Noone does anything.
What's the next step? I can't blacklist google groups!