MySQL 5.x before 5.0.36 allows local users to cause a denial of service (database crash) by performing information_schema table subselects and using ORDER BY to sort a single-row result, which prevents certain structure elements from being initialized and triggers a NULL dereference in the filesort function.

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.

MySQL before 5.0.25 and 5.1 before 5.1.12 evaluates arguments of suid routines in the security context of the routine's definer instead of the routine's caller, which allows remote authenticated users to gain privileges through a routine that has been made available using GRANT EXECUTE.

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.

Off-by-one buffer overflow in the Instance_options::complete_initialization function in instance_options.cc in the Instance Manager in MySQL before 5.0.23 and 5.1 before 5.1.12 might allow local users to cause a denial of service (application crash) via unspecified vectors, which triggers the overflow when the convert_dirname function is called. NOTE: the vendor has disputed this issue via e-mail to CVE, saying that it is only exploitable when the user has access to the configuration file or the Instance Manager daemon. Due to intended functionality, this level of access would already allow the user to disrupt program operation, so this does not cross security boundaries and is not a vulnerability

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 mysql_real_escape function is used to escape the input.

Buffer overflow in the open_table function in sql_base.cc in MySQL 5.0.x up to 5.0.20 might allow remote attackers to execute arbitrary code via crafted COM_TABLE_DUMP packets with invalid length values.