[CentOS] SPAM on the List

[Always Learning]

On Sun, 2011-07-17 at 11:06 -0600, Devin Reade wrote:

> That's fine if your check is that a reverse DNS entry exists,
> or that the HELO/ELHO exists in forward DNS or, if your MTA is
> smart enough, it does a reverse-forward* check, but if
> you only check that the HELO/ELHO matches the reverse entry
> then you're blocking a bunch of valid mailers because there is
> no specification requirement that those two match (and they don't
> in the general case).

What is the point of some super stupid over-paid Computer Professional
(usually a Windoze lover) configuring his or her (although women are
more careful than men) mail server to send emails with false
credentials ?

Example: HELO/EHLO my identity is stupid.example.com

when that server is operating on IP address xxx.yyy.zzz.aaa

and stupid.example.com has a DNS 'A' record for IP address
bbb.eee.sss.ttt ?

Incidentally the mail server's IP address xxx.yyy.zzz.aaa has a host
name of ridiculous.example.com

> you're blocking a bunch of valid mailers

What is 'valid' in this situation ?

> there is no specification requirement that those two match
> (and they don't in the general case).

When you telephone someone from your office, do you usually give a false
name and contact telephone number ?  No, of course you do not. Why
tolerate false details from a source who is often a spammer.

Mail Admins should unite against spammers not deliberately emulate them.

Here a a few examples:   http://sys.u226.com/t21/t21p003.php


-- 
With best regards,

Paul.
England,
EU.