--On Saturday, 22 November, 2003 16:51 -0500 "Richard O. Hammer"
<ROHammer(_at_)EarthLink(_dot_)net> wrote:
On Sat, 22 Nov 2003 10:31:54 EST, "Richard O. Hammer"
<ROHammer(_at_)EarthLink(_dot_)net> said:
Is there something which prevents spammers from sending
their messages with a null reverse path in the envelope?
In other words, with MAIL FROM: <>
in the SMTP exchange?
Thanks to the three who have posted responses to my question.
By reading between the lines I am guessing that there is
indeed nothing, in SMTP or other protocols or standard
infrastructure, to keep spammers from sending their messages
with a null reverse path in the envelope. The defenses
against this kind of abuse are ad hoc, possibly in violation
of an RFC, and continuously being developed and tested by any
who can conceive of ways to deal with it. Is it accurate for
me to surmise that?
Yes. More generally, there is nothing that prevents anyone,
spammers included, from setting the envelope return path to
anything they like. The difficulty with rejecting a message
with a null return path (for that reason alone) is that it puts
the recipient out of compliance and risks missing important
error messages and notifications (including, but not limited to,
bounces).
Thank you,
Rich Hammer
111 W. Corbin St.,
Hillsborough, N.C.
mailscreen.net
(Notice, if you will, an oddity. I have a name and a physical
address. If you feel that I have wronged you, you can come
find me.)
And, if you were a spammer, you could supply bogus versions of
both, and, if they were required (by law or spam-checking
software), almost certainly would.
john