[Discuss] DMARC issue, Yahoo and beyond

[blu at nedharvey.com (Edward Ned Harvey (blu))]

> From: discuss-bounces+blu=nedharvey.com at blu.org [mailto:discuss-
> bounces+blu=nedharvey.com at blu.org] On Behalf Of Bill Horne
> 
> > I think you mean to say, nothing special is done.
> 
> That's not necessarily a bad thing. If Yahoo is a stalking horse for
> GooHotMess, the Yahoo execs may be looking to see how many email
> admins
> knuckle under and feed their fantasy of total control.

Did you even read the rest?  I'm in shock to hear so many heads buried in the sand.  Ignoring them does NOT hurt yahoo in any way.  Ignoring them hurts everyone else.

If somebody posts to the list using a dmarc policy of reject, *you* will be unsubscribed from the list instead of them, because *your* email address is the one that will bounce.  Not theirs.  Read the rest of the message.  Quoted below for your convenience.

There's a really simple straightforward fix that literally has no impact on the rest of us; it has all upside and no downside.  Only users posting from an address with a reject or quarantine policy will have their from address munged.  Which makes the list safe for everyone else.


> From: discuss-bounces+blu=nedharvey.com at blu.org [mailto:discuss-
> bounces+blu=nedharvey.com at blu.org] On Behalf Of Edward Ned Harvey
> 
> I think you mean to say, nothing special is done.  Which means, if anybody
> posts to the list from a yahoo address (or any domain where dmarc is set to
> reject or quarantine) then any recipients on google, microsoft, or other
> domains where sender dmarc policy is honored, will bounce.  And the end
> result is, anybody sends from Yahoo will result in *other* people getting
> unsubscribed from the list because their mail bounces.
> 
> The official mailman suggestion, created specifically for this purpose, is to set
> from_is_list = no, and set dmark_moderation_action = munge.
> 
> This way, all the users currently using the list experience no change.  You and
> I post to the list, and it goes through same as always.
> 
> But somebody posts to the list from a domain where dmarc policy is reject or
> quarantine, their from address will be munged, so it's safe for everyone else
> to receive it.