Q: Are there known problems with "valid" mails with illegal MessageIDs?
The reason I ask is that our most successful anti-spam filters to date are:
Bad-Message-ID's (era eriksson, procmail-d Digest V97 #308, et. al.)
Ban-Repeat-Spam (very many contributors over time)
But, the bad-message-id filter catches few (very very few) emails from
valid users (who apparently, for some strange reason, are sending out email
with bad message id's). That wouldn't be much of a problem, except that
our MITS department won't even consider fixing the bad-message-id unless
it causes a problem somewhere else.
I ask:
a) Are there any real problems with a user sending mail, unknowningly
containing a bad message id?
b) How can this occur in the first place -- how could our user accidentally
send out email with a bad message id?
This is the filter that is catching (apparently) the space in the Message-Id:
#############################################################################
# From era eriksson <era(_at_)iki(_dot_)fi> in procmail-d Digest V97 #308:
# Note: There are spaces and tabs in that filter below:
#
^Message-Id:[SpaceTab]*<[^SpaceTab<>@]+(_at_)[^SpaceTab<>@]+>[SpaceTab]*$
:0:
* ! ^Message-Id:[ ]*<[^ <>@]+(_at_)[^ <>@]+>[ ]*$
$SPAMDIR/IN.badMessageId
##############################################################################
And, here is both the response from our MITS department, & the problem header:
From: "Omar Keblawi -MITS" <keblawi>
Date: Tue, 9 Dec 1997 10:57:54 -0800
In-Reply-To: John Gianni <jjg> "Bad message id -- do you know why?"
X-Mailer: Z-Mail (5.0.0 30July97)
To: alexand, John Gianni <jjg>
Subject: Re: Bad message id -- do you know why?
John or Jennifer,
What kind of problems is this causing for you?
Omar
On Dec 9, 10:53am, John Gianni wrote:
Subject: Bad message id -- do you know why?
Do you know what is wrong with Jennifer's message id?
It might be the space at the very end, before the closing angle bracket.
Or, something in between.
Message-Id:
<3(_dot_)0(_dot_)5(_dot_)32(_dot_)19971208192547(_dot_)007db100(_at_)mailhub >
John
Message-Id:
<3(_dot_)0(_dot_)5(_dot_)32(_dot_)19971208192547(_dot_)007db100(_at_)mailhub >
X-Sender: alexand(_at_)mailhub
X-Mailer: QUALCOMM Windows Eudora Pro Version 3.0.5 (32)
Date: Mon, 08 Dec 1997 19:25:47 -0800
To: John Gianni <jjg>
From: Jennifer Alexander <alexand>
Subject: Re: Bad message id number 2
In-Reply-To:
<199712090056(_dot_)QAA12117(_at_)cds9200(_dot_)Cadence(_dot_)COM>
John-
What is a bad message ID? If you let me know I will get intouch with MITS,
but you are the first person to ever tell me this?
Thanks,
Jennifer
Resource Coordinator
Software Services - North America
-- End of excerpt from John Gianni