Problem with distribution lists and members with over quota mailbox

[acasado81]

Hi everybody!

First, I want to congratulate to this forum because is very intersting and helpful. Second, i wish this problem were not repeated in the forum. And third, sorry for my english.

My problem is, that recently I created some distribution lists and i restricted the user that were able to send mail to those distributions lists. But when a permitted user send a mail to a distribution list and there are members with over qouta mailbox, the "Undelivered mail returned to sender" mail sent by mail server is sent to distribution list address. So, the "Undelivered mail returned to sender" mail is sent to all members of the distribution list.

Is normal that behavior? Can i setup the distribution list config to send "Undelivered mail returned to sender" only to the owner of the original mail?

[mmorse]

Is the sender using a a different reply-to field in a persona or masquerading as the distribution list somehow?

Because yes otherwise that shouldn't happen, this 5.0.18 per profile or have you upgraded since then?

On a 6.0.7 box
user1 sends to:
list with members:
user2 < over quota
user3
= no bounce to user1 or user3

[acasado81]

Hi, Micke!

You were right! Someone has sent to the distribution list a malicious mail from other mail server and he masqueraded the 'mail from' address and introduced the distribution list address. So, the header of the mail shows that the Return-path is the distribution list address.

I have read about that and think that the better behavior I can setup is adding a SPF. Is that correct?

Thanks for your quick response.