Ansible before 1.9.2 does not verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate.
https://lists.debian.org/debian-lts-announce/2019/09/msg00016.html
http://www.openwall.com/lists/oss-security/2015/07/14/4
http://www.ansible.com/security
http://lists.opensuse.org/opensuse-updates/2015-08/msg00029.html
http://lists.opensuse.org/opensuse-updates/2015-07/msg00051.html