Stack-based buffer overflow in the acl_get function in Oracle MySQL 5.5.19 and other versions through 5.5.28, and 5.1.53 and other versions through 5.1.66, and MariaDB 5.5.2.x before 5.5.28a, 5.3.x before 5.3.11, 5.2.x before 5.2.13 and 5.1.x before 5.1.66, allows remote authenticated users to execute arbitrary code via a long argument to the GRANT FILE command.