On Sat, 2023-08-19 at 19:10 +0300, Victor Ustugov via Exim-users wrote: > Jeremy Harris via Exim-users wrote on 19.08.2023 18:37: > > On 19/08/2023 16:29, Victor Ustugov via Exim-users wrote: > > > But > > > this won't work if there is no Message-ID header in the original > > > email. > > > > You can safely block any external-source messages lacking a > > Message-ID header (local ones, where you're being an MSA, > > not so; some MUAs are dumb and the MSA has to fix then up. > > Exim does that). > > > > RFC 5322 only lists this as a SHOULD (section 3.8.4) - > > but I see it as spamsign. > > I can't block emails that don't contain Message-Id headers. You can't > even imagine how many emails that do not meet the requirements of the > RFC come from official organizations, suppliers, buyers. > > For example, emails from nore...@cisco.com with a DMARC Aggregate > Report have a Message-ID header. But it doesn't contain angle > brackets. > > Thus, the absence of the Message-ID header or the incorrect format of > the Message-ID header are not reliable criteria for refusing to > deliver a message. >
FWIW, Google treat it as a MUST and (at least some of the time) refuse such messages at SMTP time. Regards, Adam -- ## subscription configuration (requires account): ## https://lists.exim.org/mailman3/postorius/lists/exim-users.lists.exim.org/ ## unsubscribe (doesn't require an account): ## exim-users-unsubscr...@lists.exim.org ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
