The problem:

1) I set SMTP record in my mailing software to mail.openrelay.com (example) which is open relay, so i can use it without authorization

2) I set FROM: and REPLY-TO: to "email_that_dosnot_exist@domain.com"

Now i can send spam and almost nobody can trace me back.

The question: how to protect my server from such connections on smtp level? I want to block all email messages from fake addresses before receiving the mail by the server. Is it possible? I have spent 2 days to find sutable solution, but no luck :rolleyes:

Is it possible with Exim 4x?
http://www.exim.org/exim-html-4.00/doc/html/spec_37.html

thank you.

Originally posted by H2
Now i can send spam and almost nobody can trace me back.



spam is always tracable, what would you send?

Originally posted by Tux-e-do
spam is always tracable, what would you send?

I know the way to send email that can't be traced back to me... This is possible - that is why I hate spam/spammers :(

Do you have an answer to my question?

lol, why not just add a word filter if you can, that gets rid of atleast 90% of my spam...:stickout

This is impossible to put 1000000 fake addresses manually into this file (server-wide). I'd like to check if account exist before accepting the mail from this account.

I'm not aware of any MTA that does this as a configuration option, but programatically, you can use the SMTP protocol by seeing if the MTA that is sending to you will accept a RCPT of the email address.

But this is pointless. All the spammer would need to do in your scenario is to take anyones email address off the front of their web site (i.e. it exists) and stick that in the From: field - and many spammers do this.

You're better off using an RBL, setting your equivalent of sendmails "dnl FEATURE(`accept_unresolvable_domains')dnl" as shown and using a spam filter, of which there are many.

NOOOOOO, not the addresses!!!! thatd be stupid. Put key words , some which i cant say, :

Common Words used in Spam Emails:
APR
FAST MONEY
18 ONLY
YOUNG GIRLS
ADLT:
ADULT
TEEN GIRLS
ADV:
PILLS
SEXY
DEBT
CERDIT CARD

... you get the point

Originally posted by H2


I know the way to send email that can't be traced back to me... This is possible - that is why I hate spam/spammers :(

Do you have an answer to my question?

1) No email is untraceable if it comes over the net. Please stop trying to say it is. Spam is even less anonymous because if the person is selling something they need a point of contact.

2) You also are saying something about people connecting to an open relay and sending. How does that bother you? If it is your server, close the open relaying policy or get blacklisted.

eof.

-davidu