[exim] Denying spoofs of our domain in DATA without dropping…

Top Page
Delete this message
Reply to this message
Author: David Grant
Date:  
To: <exim-users@exim.org>
Subject: [exim] Denying spoofs of our domain in DATA without dropping listserv traffic
Hi,

I was testing the following in acl_check_data:

  accept
    hosts = +relay_from_hosts
  accept authenticated = *
  warn    set acl_m_from_address = ${lc:${address:$h_From:}}
...
  deny    condition = ${if match{$acl_m_from_address}{@???}{yes}{no}}


This worked to prevent spam where the sender spoofed an eff.org address
only in DATA, but created a problem when users signed up for mailing
lists on remote servers. Their own messages to the list would be dropped
when emailed back to them (or any other eff.org subscribers) because
mailman was effectively spoofing our domain.

Has anyone else encountered this and found a good solution?

Thanks,
Starchy