On 1/16/2024 8:18 AM, Mike Hillyer wrote:
In an effort to make it easier for our users to prevent DKIM replay
attacks, we're looking at adding an option to our DKIM signing module to
  automatically oversign headers in the DKIM signature, adding an
additional entry in the headers list to assert a null header, preventing
  a malicious third party from adding an additional header but having the
  message still validate as DKIM because only one instance of the header
was listed in the signature.

While I applaud your goal, it is not immediately obvious to me how this can reduce or eliminate DKIM Replay.

Could you provide an example?

Thanks.

d/

--
Dave Crocker
Brandenburg InternetWorking
bbiw.net
mast:@[email protected]
_______________________________________________
Ietf-dkim mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/ietf-dkim

Reply via email to