MySQL 4.1 before 4.1.21 and 5.0 before 5.0.24 allows a local user to access a table through a previously created MERGE table, even after the user's privileges are revoked for the original table, which might violate intended security policy.

MySQL before 4.1.21, 5.0 before 5.0.25, and 5.1 before 5.1.12, when run on case-sensitive filesystems, allows remote authenticated users to create or access a database when the database name differs only in case from a database for which they have permissions.

Format string vulnerability in time.cc in MySQL Server 4.1 before 4.1.21 and 5.0 before 1 April 2006 allows remote authenticated users to cause a denial of service (crash) via a format string instead of a date as the first parameter to the dateformat function, which is later used in a formatted print call to display the error message.

SQL injection vulnerability in MySQL 4.1.x before 4.1.20 and 5.0.x before 5.0.22 allows context-dependent attackers to execute arbitrary SQL commands via crafted multibyte encodings in character sets such as SJIS, BIG5, and GBK, which are not properly handled when the mysqlrealescape function is used to escape the input.

sqlparse.cc in MySQL 4.0.x up to 4.0.26, 4.1.x up to 4.1.18, and 5.0.x up to 5.0.20 allows remote attackers to obtain sensitive information via a COMTABLEDUMP request with an incorrect packet length, which includes portions of memory in an error message.

The checkconnection function in sqlparse.cc in MySQL 4.0.x up to 4.0.26, 4.1.x up to 4.1.18, and 5.0.x up to 5.0.20 allows remote attackers to read portions of memory via a username without a trailing null byte, which causes a buffer over-read.

MySQL 5.0.18 and earlier allows local users to bypass logging mechanisms via SQL queries that contain the NULL character, which are not properly handled by the mysqlrealquery function. NOTE: this issue was originally reported for the mysqlquery function, but the vendor states that since mysqlquery expects a null character, this is not an issue for mysqlquery.

Unspecified vulnerability in the MySQL Server component in Oracle MySQL 5.5.19 and earlier allows remote authenticated users to affect availability via unknown vectors related to Server Optimizer.