Buffer overflow in copy.c in Mutt before 1.5.23 allows remote attackers to cause a denial of service (crash) via a crafted RFC2047 header line, related to address expansion.
http://www.ubuntu.com/usn/USN-2147-1
http://www.securitytracker.com/id/1029919
http://www.securityfocus.com/bid/66165
http://www.mutt.org/doc/devel/ChangeLog
http://www.debian.org/security/2014/dsa-2874
http://rhn.redhat.com/errata/RHSA-2014-0304.html
http://lists.opensuse.org/opensuse-updates/2014-03/msg00085.html
http://lists.opensuse.org/opensuse-updates/2014-03/msg00083.html
http://lists.opensuse.org/opensuse-security-announce/2014-04/msg00001.html