Multiple vulnerabilites has been found and corrected in mysql: sql/password.c in Oracle MySQL 5.1.x before 5.1.63, 5.5.x before 5.5.24, and 5.6.x before 5.6.6, and MariaDB 5.1.x before 5.1.62, 5.2.x before 5.2.12, 5.3.x before 5.3.6, and 5.5.x before 5.5.23, when running in certain environments with certain implementations of the memcmp function, allows remote attackers to bypass authentication by repeatedly authenticating with the same incorrect password, which eventually causes a token comparison to succeed due to an improperly-checked return value . MySQL 5.1.x before 5.1.63 and 5.5.x before 5.5.24 allows remote authenticated users to cause a denial of service via vectors related to incorrect calculation and a sort order index . Stack-based buffer overflow 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 . The updated packages have been patched to correct these issues.