Alt-N has released MDaemon 15.0.3, 14.5.4, 14.0.4, 13.5.4, as well as patches for MDaemon 12.5, 12.0, 11.0 to correct a critical security vulnerability. I would highly recommend installing the latest bits as soon as is possible. While I don’t know all the details, be aware that the content filter processes all messages, therefore the vulnerability can likely be remotely exploited.
Read MDaemon Security Bulletin – MD061915 for more details, then get your server patched!
MDaemon Support Bulletin – MD061915 by Dave Warren (everything-mdaemon.com) is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.