Educause Security Discussion mailing list archives
Re: DMARC, Yahoo and mailing lists
From: Roger A Safian <r-safian () NORTHWESTERN EDU>
Date: Thu, 19 Jun 2014 14:43:10 +0000
We applied the patch on May 1st...so far no problems. Here's what we had sent out to our community: NUIT has applied a patch to the Listserv system that remedies the problem described below for Listserv users. All @yahoo/@aol email posting has been restored to NU Listserv. ****IMPORTANT - NU Listserv List Owners. See NU Listserv Response section.**** Northwestern University Information Technology (NUIT) and other email service providers have identified some disruption of communications due to Yahoo and AOL's implementation of a new DMARC, or Domain-based Message Authentication, Reporting & Conformance policy. Yahoo and AOL have reported that these changes to their systems are intended to reduce email fraud, and are beyond the control of the University. Impact on End User This change can affect anyone sending or receiving email from @yahoo.com or @aol.com. Messages sent from these email providers may not be delivered if the intended recipient is forwarding their email through a rule on their mailbox; a distribution list; a listserv application; or other application. NUIT will continue to work with Yahoo and AOL in an effort to remove these service barriers. Northwestern Provided Email Services Northwestern University provides email services to faculty, staff, and students that are designed to provide stable and reliable email delivery. In the event you are forwarding your University provided account to an alternate email service provider we recommend you remove the forwarding rule to allow messages from yahoo.com and aol.com to be delivered to you. Northwestern Listserv Response To provide timely delivery of messages to the University community we have taken steps to transition the affected email addresses to "read-only mode" within the University Listserv application. If you are currently subscribed to a University listserv and wish to post messages, please subscribe with a non-Yahoo or AOL email address. For more information NUIT has posted a What's New & Changing page on our website: www.it.northwestern.edu/transitions/2014/Yahoo-DMARC.html Please communicate as appropriate to your list.
-----Original Message----- From: The EDUCAUSE Security Constituent Group Listserv [mailto:SECURITY () LISTSERV EDUCAUSE EDU] On Behalf Of Andrew Daviel Sent: Wednesday, June 18, 2014 7:11 PM To: SECURITY () LISTSERV EDUCAUSE EDU Subject: [SECURITY] DMARC, Yahoo and mailing lists Has anyone had problems with Yahoo email users and mailing lists since April, and if so what did you do about it ? http://blog.threadable.com/how-threadable-solved-the-dmarc-problem Apparently there's a patch available for mailman, but I haven't tried it yet. I hadn't been made aware of any mailing list problems here, but now I start looking into it with some test accounts, it seems I cannot send a message via mailman from a yahoo account to another yahoo account, or from a yahoo account to a hotmail account. Not just being filtered as spam, but actually getting an SMTP rejection. When I check, I see that at least the following now have "reject" DMARC records: facebook.com linkedin.com paypal.com yahoo.com twitter.com viz. DNS TXT records for xxx.tld, e.g. "host -t txt _dmarc.yahoo.com" or "dig +short -t txt _dmarc.twitter.com" This probably has implications for Unix-style mail forwarding, too - forwarded linkedin and facebook notifications may fail if the target domain implements DMARC filtering. -- Andrew Daviel, TRIUMF, Canada Tel. +1 (604) 222-7376 (Pacific Time)
Current thread:
- DMARC, Yahoo and mailing lists Andrew Daviel (Jun 18)
- Re: DMARC, Yahoo and mailing lists Roger A Safian (Jun 19)
- Re: DMARC, Yahoo and mailing lists Walter Moore (Jun 19)