The default configuration of the Windows binary release of MySQL 3.23.2 through 3.23.52 has a NULL root password, which could allow remote attackers to gain unauthorized root access to the MySQL database.

The default configuration in MySQL 3.20.32 through 3.23.52, when running on Windows, does not have logging enabled, which could allow remote attackers to conduct activities without detection.

The COM_CHANGE_USER command in MySQL 3.x before 3.23.54, and 4.x before 4.0.6, allows remote attackers to gain privileges via a brute force attack using a one-character password, which causes MySQL to only compare the provided password against the first character of the real password.

libmysqlclient client library in MySQL 3.x to 3.23.54, and 4.x to 4.0.6, does not properly verify length fields for certain responses in the (1) read_rows or (2) read_one_row routines, which allows remote attackers to cause a denial of service and possibly execute arbitrary code.

The COM_CHANGE_USER command in MySQL 3.x before 3.23.54, and 4.x to 4.0.6, allows remote attackers to execute arbitrary code via a long response.

Signed integer vulnerability in the COM_TABLE_DUMP package for MySQL 3.23.x before 3.23.54 allows remote attackers to cause a denial of service (crash or hang) in mysqld by causing large negative integers to be provided to a memcpy call.