SOLVED DMARC, DKIM, SPF and MxToolbox - domain shows hundreds of thousands of unauthenticated messages

[unco]

Hi Everyone,

I have a domain that began being rejected by gmail. I signed up with MxToolbox to try to troubleshoot the problem. What we know is that the messages are not going through the server here. They are allegedly going out of a server in Singapore. I'm really trying to figure out how this is happening! I tried to send email to the abuse admin at the domain, and it bounced with a no such user message. I sent to hostmaster account next & am waiting to see...

I have DKIM keys set up in cPanel. I have SPF set up with -all. DMARC is still set to policy none, but I'm wondering if, since messages are being rejected from the users anyway, should I set it to quarantine?


I ran some header analysis at MxToolbox, and they indicate :

DKIM Signature Body Hash Verified

Body Hash Did Not Verify

This makes me think there is an error with the cPanel generated keys. Do these keys need to be copied to the DNS servers? This machine doesn't do DNS. When a recipient's server is checking DKIM keys, they are looking at the message header, but do they expect to find the public key on the DNS server someplace?

There's so much that could be wrong, so I'm wondering if anyone has any ideas about what to do, or are there any good consultants that could help out?

Thanks,
B

 

[cPanelLauren]

From what I understand mxtoolbox's body hash verification has a bug. You can see this discussed in a few places:

DKIM Body Hash Did Not Verify

I have configured DKIM as suggested somewhere in the forums where I set the key path, selector and Sign. The message is signed but it seems it is modified when received. I get the header from the received message and I analyze it on mxtoolbox.com and I get a message for DKIM verification: Body...

www.axigen.com

DKIM Body Hash Did Not Verify · Issue #252 · Pro/dkim-exchange

Versions Windows Server Version: 2019 Exchange Version: 2016 CU10 Installed DKIM Exchange Version: 3.1.0 Description DKIM Body Hash Did Not Verify I am not an expert. And I can't figure out why thi...

github.com

In that second link it's noted that the issue with it is resolved but the first link is another report of it being buggy again recently.

Have you tried using a different DKIM validator?

 

[unco]

Thanks for the reply! I appreciate it. I have tried a few validators, and it seems to bear out your point that MX Toolbox has some buggy stuff. Do you have any recommendations for ongoing monitoring?

I submitted a request to google, begging for them to help. I'll let you know what happens with that.

Thanks for taking the time to help.

Beth

 

[cPanelLauren]

I don't see an issue with using MxToolBox just with the understanding that specific item has an issue. You would still be able to utilize monitoring.


Newsletters spam test by mail-tester.com does a great job of checking email for authentication

DKIM, SPF, and Spam Assassin Validator - dkimvalidator.com does a great job of checking DKIM as well as SPF and spam

 

[unco]

Thanks for the info. We can call this one solved!