[Mailman-Users] Wrong "From" in header, Why?

[Mark Sapiro]

On 09/20/2016 10:53 AM, Gao wrote:
> 
> I have a strange thing happened and I could not figure it out what is
> going on. Here is what happened:
> 1. Syd V <sydv at mydomain.com> sent an email to our mailing list
> sjv-geosupport at mydomain.com
> 2. Trent replied to the list
> 3. All list members received Trent's reply, BUT with wrong FROM address.
> It appears Trent's reply is from Syd. ???
> 4. I talked to Trent and asked him to do another reply to list, and this
> time everything is correct. He can not re-produce this error.
> 
> I post the header section from Trent's reply as well as the maillog here.


It is clear from your maillog that the message received with queue ID
36FFF20158EC6 was sent (envelope from) from trent, but this says nothing
about the headers in the body of the message.

The headers in the body have From: and Reply-To: as 'Syd V
<sydv at mydomain.com>' and 'Syd Visser <sydv at mydomain.com>' respectively.

Since I can think of no way that Mailman would rewrite these headers and
even if it did, I would think the two headers would have the same
display name, I have to think the somehow Trent's MUA
(Thunderbird/45.2.0) is responsible. I can't say how this happened, but
I think the message arrived with those headers, and even if they were
somehow changed in your server, there are other, more likely suspects
than Mailman.

>From your mail log, I see the message arrives with ID 36FFF20158EC6, is
scanned by MailScanner, requeued with ID 3603320158ECB and '(delivered
via autoresponder service)'. Then a message is received, presumably from
the autoresponder service, with ID EB63E20158EC6, scanned by
MailScanner, requeued with ID BE0D320158ECB and delivered to Mailman.

I.e., the message has been through MailScanner twice and "autoresponder
service" before it ever gets to Mailman.

Both 36FFF20158EC6.A07F8 and EB63E20158EC6.A4FB8 were logged to
MailWatch. I don't use MailWatch and don't know what's in those logs,
but perhaps there is a clue there.

-- 
Mark Sapiro <mark at msapiro.net>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan