Douglas Otis writes: > DMARC being unable to assert the domain
I'm not sure what you mean by "assert the domain". AFAICS no new protocol is needed to validate Sender -- SPF and DKIM allow that already, and it's not obvious to me where the big threat is from a misaligned or spoofed Sender. (A BCP might say that Sender should be aligned with the SPF domain if available, and otherwise with a valid DKIM signer otherwise). I suppose some receivers already use this information in their reputational models. > Many have not realized double signing is wide open to abuse Please present your threat analysis. As far as I can see, double signing is no more vulnerable than the current practice for mailing lists when relaying mail from p=none sites. It would increase the attack surface for the kind of abuse that caused some major sites to publish p=reject last April, but it's something that can be turned on incrementally as a matter of local policy (just as DMARC itself was), and it can be turned off as fast as you can propagate the config change to your SMTP server farm (unlike p=reject itself, which suffers from DNS caching lag). I wouldn't call that "wide open". Steve _______________________________________________ dmarc mailing list [email protected] https://www.ietf.org/mailman/listinfo/dmarc
