PHP Improper Certificate Validation Vulnerability - CVE-2015-3152
Oracle MySQL before 5.7.3 Oracle MySQL Connector/C (aka libmysqlclient) before 6.1.3 and MariaDB before 5.5.44 use the --ssl option to mean that SSL is optional which allows man-in-the-middle attackers to spoof servers via a cleartext-downgrade attack aka a quotBACKRONYMquot attack.