Tony Hansen writes:

 >> That doesn't help the DMARC situation now, but DMARC could be
 >> given other options once that happens.
 > 
 > I agree completely that a change to DMARC is needed in conjunction
 > with having clear ML specs.

A change to the protocol?  What?  I don't see it.  The protocol
actually in use by many domains seems to actually do what it's
designed for quite well.  "p=reject" makes a lot of sense for banks,
for example.  I don't think it can be removed from the spec, and its
proper use doesn't cause widespread problems for mailing lists.

It's use outside the design space that causes problems.  Those uses
are by desperate organizations, and they'll ignore any change that
attempts to prohibit them because they are desperate.

 > I've heard it said that the majority of the mailing lists out there
 > are managed by only a handful of ML management systems. I maintain
 > that these ML packages are in the same boat as openssl. It sure
 > would be nice if we could get some of that consortium money thrown
 > at that handful of ML management systems.

I'm sorry, but that's nonsense for the volunteer-maintained MLMs like
GNU Mailman.  We already have implemented multiple mitigations, and it
doesn't take much code.  We just hate them all and leave it up to
mailing list operators to choose the one they dislike least.  If other
MLMs haven't done so already, I doubt it involves all that much effort
for them.

 > That's a political solution for this current technical problem.

Mailing lists don't have a *technical* problem.  If DMARC were used as
designed, we'd never have noticed.  The problem is political: we have
a wounded 800-lb gorilla on the loose (not to forget a wounded 500-lb
gorilla joining the fun).

 > However, before it can happen: we NEED clear specs as to what
 > should be done by ML systems, at least in the face of DKIM and SPF
 > (and DMARC)

SPF and DKIM are now ancient history, at least as far as Mailman
development goes.  We've already done what's technically possible.
We'll see what more our users want us to do about DMARC, if anything.
There just isn't anything technical to be done AFAICS.

I can't speak for other MLMs, but I think that if there's going to be
real progress, the answer is with the MUAs.

1. If identity alignment fails, *all* links, scripts, and forms in the
   message should be deactivated, even if it's already in the spam
   folder.

2. If there's a type=password field in the message, *all* links and
   forms in the message should be deactivated, even if it's already in
   the spam folder.

3. Ditto misaligned MIME type and file name.

4. Ditto active or unknown attachments.

5. On activation of the message, all href and src URIs should be
   displayed clearly, along with an intrusive warning that ID theft is
   very common, so the user should check everything carefully
   (preferably call the author on the phone) before doing anything
   suggested by the message, even if it's already in the spam folder.

I'm sure there are other things they could do, but those are off the
top of my head.

Finally, Tim Draegen is right, it's not just about mailing lists.
Let's not forget all the other use cases that are stomped on by the
inappropriate use of "p=reject".

Steve

_______________________________________________
dmarc mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/dmarc

Reply via email to