Red Hat Security Advisory 2015-1153-01 - Mailman is a program used to help manage email discussion lists. It was found that mailman did not sanitize the list name before passing it to certain MTAs. A local attacker could use this flaw to execute arbitrary code as the user running mailman. Previously, it was impossible to configure Mailman in a way that Domain-based Message Authentication, Reporting & Conformance would recognize Sender alignment for Domain Key Identified Mail signatures. Consequently, Mailman list subscribers that belonged to a mail server with a "reject" policy for DMARC, such as yahoo.com or AOL.com, were unable to receive Mailman forwarded messages from senders residing in any domain that provided DKIM signatures. With this update, domains with a "reject" DMARC policy are recognized correctly, and Mailman list administrators are able to configure the way these messages are handled. As a result, after a proper configuration, subscribers now correctly receive Mailman forwarded messages in this scenario. Continue reading...
