CVE-2016-4747
Mail in Apple iOS before 10 mishandles certificates, which makes it easier for man-in-the-middle attackers to discover mail credentials via unspecified vectors.
Date published : 2016-09-18
http://lists.apple.com/archives/security-announce/2016/Sep/msg00002.html
http://lists.apple.com/archives/security-announce/2016/Sep/msg00008.html