2

If an email contains multiple DKIM signatures as it's forwarded, how does DMARC process the DKIM alignment check?

Does ANY passing DKIM signature d= parameter have to match Header From?

or

Does the first (or last) DKIM signature d= parameter have to match Header From?

or

Does the single DKIM as indicated in the "Authentication-Results" have to pass (which may always be the last?)?

This is NOT a question of relaxed vs. strict.

Thank you!

  • were you ever able to find the answer to this question? – caradrye Sep 14 '18 at 19:50
0

According to DMARC specification: https://tools.ietf.org/html/rfc7489

Note that a single email can contain multiple DKIM signatures, and it is considered to be a DMARC "pass" if any DKIM signature is aligned and verifies.

2

If there are multiple DKIM signatures, only one of them must align for DKIM alignment to be valid according to https://mxtoolbox.com/problem/dkim/dkim-signature-alignment

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.