To supplement Oliver's reply, and Doug's question, most commercial secure
email gateways are capable of this in terms of granular inbound email
authentication customization. (Proofpoint, Mimecast, Cisco, Barracuda, etc.)

- Mark Alley



On Thu, Jul 20, 2023, 4:15 AM OLIVIER HUREAU <
[email protected]> wrote:

> Hi,
>
> > Can you find a commercial product that can configure a rule which says,
> "Don't worry about DMARC if Mail from = bounceaddtess@listdomain and the
> MailFrom address produces SPF PASS"?
>
> The solution I can propose to you is using Cisco AsyncOS (
> https://www.cisco.com/c/en/us/td/docs/security/esa/esa14-0/user_guide/b_ESA_Admin_Guide_14-0.html)
> software.
>
> Ciscos's solution does have Email authentication global settings where you
> can bypass the DMARC verification if the message contains a specific header.
>
>
> https://www.cisco.com/c/en/us/td/docs/security/esa/esa14-0/user_guide/b_ESA_Admin_Guide_14-0/b_ESA_Admin_Guide_12_1_chapter_010110.html#con_1225789
>
> Let's assume the header we are looking for is 'X-MAILFROM-SPF-PASS:TRUE'
>
> The idea is then to use the Message Filters features of AsyncOs to add a
> specific header using the action 'insert-header'
>
> You can then use the SPF-Status Rule (
> https://www.cisco.com/c/en/us/td/docs/security/esa/esa14-0/user_guide/b_ESA_Admin_Guide_14-0/b_ESA_Admin_Guide_12_1_chapter_01000.html#con_1132105)
> and EnvelopeFrom such as :
>
> overpass_dmarc_if_spf_mailfrom_pass:
> if (EnvelopeFrom == "bounceaddtess@listdomain" AND spf-status("mailfrom")
> == "Pass"){
> insert-header("X-MAILFROM-SPF-PASS","TRUE")
> }
>
> I am not a Cisco expert but, to be confirmed.
>
> Regards,
> Olivier Hureau
>
> ------------------------------
> *De: *"Douglas Foster" <[email protected]>
> *À: *"Dotzero" <[email protected]>
> *Cc: *"IETF DMARC WG" <[email protected]>
> *Envoyé: *Jeudi 20 Juillet 2023 04:41:57
> *Objet: *Re: [dmarc-ietf] How did DMARC go wrong, and how does our
> document fix it?
>
> Can you find a commercial product that can configure a rule which says,
> "Don't worry about DMARC if Mail from = bounceaddtess@listdomain and the
> MailFrom address produces SPF PASS"?
>
> Simple enough rule.  If vendors understood what we want them to
> understand, they would allow creation of multipe-attribute rules like this,
> combining authentication results and identifier values, to provide local
> authentication overrides.   But they don't, or at least I have not found
> one after diligently searching.
>
> On the other hand, finding products that block unconditionally on FAIL is
> pretty easy.
>
> We need to find words in our document that begin to fix this, to obtain
> the products and evaluator behavior that we both want and their users need.
>
> Doug
>
> On Wed, Jul 19, 2023, 8:07 PM Dotzero <[email protected]> wrote:
>
>>
>>
>> On Wed, Jul 19, 2023 at 6:21 PM Douglas Foster <
>> [email protected]> wrote:
>>
>>> Perhaps you can clarify what you think DMARC is.
>>> Apparently a significant number of evaluators think that "DMARC Fail
>>> with p=reject always means unwanted mail".   Or to use Michael Hammer's
>>> language, "DMARC Fail with p=reject means the domain owner wants it
>>> rejected so I will reject it."    These are exactly the attitudes that
>>> cause us so much trouble because (a) DMARC Fail with p=reject does not mean
>>> that rejection is always the correct response, and (b) DMARC Fail with
>>> p=none is an important piece of information.
>>>
>>
>> You are misrepresenting my position by ignoring local policy. A DMARC
>> policy of quarantine or reject is a request by the domain owner or
>> administrator. While consideration of a sending domain's request should be
>> given consideration, a receiving domain is free to do as it wishes. A
>> receiving domain may choose not to implement DMARC validation at all. A
>> sending domain may believe that the risk of some legitimate emails being
>> rejected or quarantined is an acceptable tradeoff in order to protect
>> itself and users/recipients. You appear to have a problem with these
>> choices being made by both the sending domain and the receiving domain. Why
>> do you presume to know better than they as to what they should do?
>> Certainly, if I publish a policy of p=reject and a receiver allows an email
>> that should have been rejected to reach their user/customer and that person
>> contacts me because that message caused them a problem, I'm going to tell
>> them they need to speak with their mail administrator, mailbox provider,
>> etc. I've done that in the past and I'll do it in the future. What others
>> choose to do is their choice. While I may have an opinion, I recognize that
>> it is their choice.
>>
>>>
>>> We have only two ways to block unwanted messages:   Identify unwanted
>>> and malicious messages based on the sender, or based on the content.
>>>  Impersonation interferes with the sender reputation assessment, so we know
>>> that attackers have an incentive to impersonate.   Sender Authentication
>>> provides information about messages that MIGHT be impersonations
>>> because they are not authenticated.   Fortunately, most messages can be
>>> authenticated.
>>>
>>
>> You are again misrepresenting what DMARC is and does. It is NOT a
>> guessing game about whether a recipient might want a given email. It is a
>> simple pass/fail that should be automated before a message ever
>> (potentially) gets to a recipient. It may be as simple as the message took
>> an unintended or unexpected path which potentially creates risks from the
>> perspective of the sending domain. DMARC knows nothing about whether email
>> is wanted or unwanted on the receiving side of the mailstream. It knows
>> nothing about reputation. DMARC is not a substitute for other filtering or
>> reputation systems. DMARC is not a Swiss Army knife, was never intended to
>> be one, nor is it appropriate to pretend you can contort it into one.
>>
>> I absolutely agree with John regarding his comments and agree with his
>> sentiment of " I am so tired of people imagining that DMARC is more than it
>> is."
>>
>> Michael Hammer
>>
>>
>>>
>>> Doug
>>>
>>>
>>>
>>>
>>> On Wed, Jul 19, 2023 at 5:32 PM John Levine <[email protected]> wrote:
>>>
>>>> It appears that Barry Leiba  <[email protected]> said:
>>>> >> - An attacker sends 10 messages that maliciously impersonates a
>>>> >> big bank.  With help from DMARC p=reject, the evaluator blocks
>>>> >> them all.  The attacker follows up with 10 messages that
>>>> >> maliciously impersonate a major university.   The stupid
>>>> >> evaluator says, "p=none means no problem here".   The message is
>>>> >> accepted and the user is harmed because the evaluator learned
>>>> >> nothing from blocking the successful attack.
>>>> >
>>>> >This is a useful point, and I think we should do something with it.
>>>>
>>>> Sorry, but I completely disagree.
>>>>
>>>> The interesting filtering data is that a bunch of unauthenticated mail
>>>> arrived from some source. As we have learned over and over, someone's
>>>> DMARC policy tells you nothing about the threat level or whether the
>>>> failure is an attack or a mailing list, only that someone decided for
>>>> whatever reason to publish p=reject.
>>>>
>>>> If a source sends a burst of unauthenticated mail, it could often be a
>>>> good idea to give that source a poor reputation. Or maybe you have a
>>>> reason to believe otherwise, e.g., it's been sending bursts of
>>>> unauthenticated mail for years, nobody's ever marked it as spam,
>>>> because it's some kind of courtesy forward.
>>>>
>>>> Note that you would do exactly the same thing if the burst of
>>>> unauthenticated university mail preceded the burst of bank mail. It's
>>>> the authentication failure that tells you that there may be a problem,
>>>> not the DMARC policy.
>>>>
>>>> Mail filtering is complicated, so much so that handling the signals is
>>>> more than a full time job at many mail systems. I expect that large
>>>> mail systems have their own ideas abou who's a bank, who's a
>>>> university, who's a public mail system, and so forth. You get exactly
>>>> none of that from DMARC. After all, yahoo is p=reject, gmail and
>>>> hotmail/outlook are p=none.
>>>>
>>>> I am so tired of people imagining that DMARC is more than it is.
>>>>
>>>> R's,
>>>> John
>>>>
>>>> _______________________________________________
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>>>> https://www.ietf.org/mailman/listinfo/dmarc
>>>>
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>>
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