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Learn and Test DMARC

learndmarc.com

11–20 of 65 posts

Re: Learn and Test DMARC

#11
post #6

Very cool. > For DMARC to pass, DKIM and/or SPF checks need to pass and the domains must be in alignment. AFAIK this is incorrect. It is not "and/or" but rather "or" - only DKIM or SPF needs to pass. There is no method to require both.

Dunno why you're being downvoted, you're correct that it's only "or".

Re: Learn and Test DMARC

#13

I sent an email via Apple’s “Hide My Email” service [1]. > Unhandled Promise Rejection: > TypeError: a.from.replace(/[ > dist.min.js:3:32767 This error occurred after the interface began displaying the following information: > Here are the message headers and message body: > DKIM-Signature: d=icloud.com s=1a1hai It’s been over a year since the website was featured on Hacker News (January 10, 2022), so I suspect that…

You sent an email without a "from" field and it broke. Programmer didn't think to test for bad users doing bad things. Nothing special here, no big conspiracy.

Re: Learn and Test DMARC

#15

I sent an email via Apple’s “Hide My Email” service [1]. > Unhandled Promise Rejection: > TypeError: a.from.replace(/[ > dist.min.js:3:32767 This error occurred after the interface began displaying the following information: > Here are the message headers and message body: > DKIM-Signature: d=icloud.com s=1a1hai It’s been over a year since the website was featured on Hacker News (January 10, 2022), so I suspect that…

You sent an email without a "from" field and it broke. Programmer didn't think to test for bad users doing bad things. Nothing special here, no big conspiracy.

[deleted]

Re: Learn and Test DMARC

#17
post #6

Very cool. > For DMARC to pass, DKIM and/or SPF checks need to pass and the domains must be in alignment. AFAIK this is incorrect. It is not "and/or" but rather "or" - only DKIM or SPF needs to pass. There is no method to require both.

And if you use IP address literals instead of paying for a domain, you get a free SPF:

If the "From:"/"Reply-To:" fields contains only the email address with the IP address literal, you get your "SPF" and it gets a much better score in order to avoid grey listing for the first transaction. And if there are no URLs in the content, even better.

But that is common sense.

Re: Learn and Test DMARC

#19

I sent an email via Apple’s “Hide My Email” service [1]. > Unhandled Promise Rejection: > TypeError: a.from.replace(/[ > dist.min.js:3:32767 This error occurred after the interface began displaying the following information: > Here are the message headers and message body: > DKIM-Signature: d=icloud.com s=1a1hai It’s been over a year since the website was featured on Hacker News (January 10, 2022), so I suspect that…

I also get the same error (in Chrome) when testing a forged email:

  telnet learndmarc.com 25
  Trying 87.239.13.42...
  Connected to learndmarc.com.
  Escape character is '^]'.
  220 allspark.uriports.com ESMTP URIports Mail Portal 1.03.2 Sun, 01 Oct 2023 21:55:40 +0000
  HELO there
  250 allspark.uriports.com Hello  []
  MAIL From: me@example.com
  250 OK
  RCPT To: ld-49101f55f6@learndmarc.com
  250 Accepted
  DATA
  354 Enter message, ending with "." on a line by itself
  .
  250 OK id=1qn4QF-00CUhd-5j
It's funny because while I was typing this, it's like "you don't have to write a love letter". Maybe not, but you do have to repeat the From: and To: header in the data segment, I guess.

I remain amused at how much email I've sent over the years with "HELO there" instead of my hostname in there. I also wonder what % of internet traffic is "Enter message, ending with . on a line by itself".

Re: Learn and Test DMARC

#20
post #6

Very cool. > For DMARC to pass, DKIM and/or SPF checks need to pass and the domains must be in alignment. AFAIK this is incorrect. It is not "and/or" but rather "or" - only DKIM or SPF needs to pass. There is no method to require both.

I think you are just misparsing their grammer. I believe and/or just means inclusive or. It does not mean "and" is neccesarily an option.
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