Everybody's aware that Google will start enforcing DMARC Feb 1st, right?

35 points by StuntPope 1 year ago | 18 comments
  • kmoser 1 year ago
    Maybe I'm just paranoid but if you configure your DMARC records to receive reports via email, doesn't that open the door for malicious actors to send bogus reports, if for no other reason than just for the lulz? I realize that the only sane way to deal with these reports is via an automated service (nobody in their right mind wants to manually parse through tons of XML reports on a regular basis) but how do I stop the incoming data from being poisoned?
    • pul 1 year ago
      The RFC requires SMTP servers to first verify that the destination email indeed wants to receive those reports. They’re opt in through a DNS record.

      https://datatracker.ietf.org/doc/html/rfc7489#section-7.1

      • StuntPope 1 year ago
        I've been monitoring this with an eye toward creating a honeypot for DMARC abuse but so far been seeing zero messages come in.

        Either the spammers haven't figured it out yet, or they realize it's a waste of time since all the messages are either mechanically processed or ignored.

        • brightball 1 year ago
          Yes it does.
        • donmcronald 1 year ago
          I think the end goal here is to push stuff like BIMI so big tech can start charging another large annual fee to all businesses that want their email delivered.
          • frizlab 1 year ago
            Yeah I inquired on how to setup BIMI for my company and was appalled by the price of this! We did not do it, it was too expensive.
            • brightball 1 year ago
              BIMI is nothing more than a carrot to get the marketing department on board with DMARC and to give the people who sold EVSSL something else to convince companies to waste money on.
              • sbuk 1 year ago
                For a change, I don't think the issue is big tech. The certificate issuers and authorities seem to see BIMI as a cash grab.
              • nerdjon 1 year ago
                I am confused about what exactly this means if we just have a personal domain for my professional emails. Which are just a couple a day at a max (really depends on if I am looking for a new job or not).

                Does this make having email accounts like this viable anymore? Am I at risk of my emails not getting where I expect them too, particularly important if I am looking for a new job?

                I use Amazon WorkMail so will need to see if that has done what is necessary, but still worried what exactly this will mean.

                Edit: Is there a tool to validate that things are setup how we need it to be?

                • brightball 1 year ago
                  Everything I have read to this point is that it will only affect you if you're sending > 5,000 message / day. Admittedly, there's no excuse for not having DMARC setup at that scale at this point as it's been a decade.

                  But as far as the policy, it doesn't have to be enforced. For most people, this just means that they'll need to a quick DNS entry to their domain for an unenforced policy.

                  Example...

                  TXT _dmarc.example.com "v=DMARC1; p=none;"

                  I did a 3 part DMARC writeup a while back if you're curious to learn more. It's not hard to setup. In fact, the smaller you are, the easier it is.

                  https://www.brightball.com/tag/dmarc-guide

                  • sbuk 1 year ago
                    I'd add that DKIM is relitively simple to configue and, along with SPF, is a worthwhile endovour. It's considered as basic hygiene by spam filters.
                  • StuntPope 1 year ago
                    You'll still be able to to run personal email from your domain - I'd add SPF and a minimal DMARC and you'll be fine.
                    • sbuk 1 year ago
                      > Edit: Is there a tool to validate that things are setup how we need it to be?

                      There are plenty, but mxtoolbox.com is your friend for most things email related.

                      • 1 year ago
                      • taskforcegemini 1 year ago
                        The DMARC requirement only applies to senders who send at least 5000 e-mails per day to gmail-recipients.

                        I'm not a fan of DMARC. SPF and DKIM already do their job well enough. Then people add DMARC with "p=none" just to tick their "have DMARC" box. Even google suggests a policy of "none" is ok, but doesn't mention that this means SPF and DKIM will be ignored.

                        • pul 1 year ago
                          SPF and DKIM are not enough to harden email. Email can still be spoofed through a loophole in both specs.

                          See https://www.nslookup.io/learning/dmarc-a-practical-guide/

                          • taskforcegemini 1 year ago
                            which loophole? I didn't see it mentioned in the article.

                            and this quote is not correct:

                            > Note that an email doesn't need to pass both DKIM and SPF. Just one is enough to validate an email.

                            Unless it was said in regards to DMARC, it usually depends on the mailfilter of the receiver. If it was said in regards to DMARC then it's just another point why DMARC is bad.

                          • johnea 1 year ago
                            That 5000 email/day limit should prevent most small business/personal servers from being affected...
                          • brightball 1 year ago
                            Just that you must have a DMARC record in place. Doesn’t have to be enforced yet.

                            That is a logical next step down the road though and IMO long overdue.

                            • 1 year ago