SOLVED Serious Mailman DMARC Bug

[brianc]

All of our mailman lists are no longer doing DMARC checks on or about Jan 6th. I believe the problem is with a cPanel update. We are seeing the following in the mailman error log:

Jan 16 19:24:18 2017 (7889) DNS lookup for dmarc_moderation_action for list <Listname>not available

This started on Jan 6th and since then we have had clients complaining of aol and hotmail mail users being removed from their lists even though DMARC settings were enabled.

I was told by the mailman developers to run "python -c "import dns.resolver"" for any errors, I get the following:

Traceback (most recent call last):
File "<string>", line 1, in <module>
ImportError: No module named dns.resolver

I believe this is a bug that was introduced by cPanel. I will be filling out a support ticket in regards to this but I am warning any other cPanel hosting providers to keep a look out for this since it can seriously disrupt an active mailman mailing list.

Brian

 

[sneader]

Same exact problem here, causing a lot of grief for us.

I opened a ticket with cPanel, Ticket ID # 8136657.

- Scott

 

[cPMelaniel]

I've filed a case for our development team to investigate further (CPANEL-10869)

I also found a workaround to the issue by downgrading the installed version of cpanel-dnspython.

Thanks for bringing this issue to our attention! I'll be keeping an eye out on this forum page tonight if anyone has questions or concerns.

 

[sneader]

Here are the steps we performed on our cPanel servers, as provided by cPanel Tech Support, to get DNS lookups (for DMARC) working in Mailman again:

# rpm -e --nodeps cpanel-dnspython-1.12.0-3.cp1158.x86_64
# wget http://httpupdate.cpanel.net/RPM/11.58/centos/6/x86_64/cpanel-dnspython-1.12-1.cp1158.x86_64.rpm
# rpm -Uhv cpanel-dnspython-1.12-1.cp1158.x86_64.rpm
# /scripts/restartsrv_mailman

- Scott

 

[cPanelMichael]

Hello,

To update, the resolution is included as part of cPanel version 62.0.5:

Fixed case CPANEL-10869: Update cpanel-dnspython to 1.12.0-4.cp1158.

You can review the full cPanel version 62 change log at:

62 Change Log - Change Logs - cPanel Documentation

Thank you.

 

[sneader]

Thanks, @cPanelMichael! We're still on v60, so we'll have to wait for this to trickle down to v60. Fortunately, the work around seems to be working well, other than the annoying nightly notices of "Altered RPMs"

- Scott

 

[cPanelMichael]

Hello @sneader,

The case is also scheduled for inclusion in a future cPanel version 60 build, but I don't have a specific time frame to offer on it's publication at this time.

Thank you.