spam problems - from spoofed address
I'm having a lot of problems with excessive spam (to our president)... It's basically a DOS... What's happening is that some spammers are sending out tons of spam and they're using our president's email address in the "From" field. Many thousands of emails "bounce-back" to his address hourly/daily...
I'm trying to figure out how to block these bounce-backs... Technically, these "bounces" are not spam themselves, they are legitimate messages from legitimate servers, bouncing back a message to our pres telling him the message he "sent" is not being delivered... Of course HE NEVER SENT THEM, - I can see the originating server's ip address, and the one who originally sent the email is some server in Africa and some server in China or east asia.
Anyway, the thing is; is there a good way to block these messages? I have to somehow block them based on the "original message", not the current message header... I've attached a sample message. They set the reply-to field to their email address to receive any actual replies, but by using firstname.lastname@example.org in the "From" field, they send all the bounce-backs to me..:(
Maybe there's a different approach I should be looking into..