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.
runner/connection_plugins/ssh.py in Ansible before 1.2.3, when using ControlPersist, allows local users to redirect a ssh session via a symlink attack on a socket file with a predictable name in /tmp/.