CVE 2012-5615

Oracle MySQL 5.5.38 and earlier, 5.6.19 and earlier, and MariaDB 5.5.28a, 5.3.11, 5.2.13, 5.1.66, and possibly other versions, generates different error messages with different time delays depending on whether a user name exists, which allows remote attackers to enumerate valid usernames.

See the CVE page on for more details.