Database administrators should use the following guidelines to keep passwords secure.

MySQL stores passwords for user accounts in the mysql.user system table. Access to this table should never be granted to any nonadministrative accounts.

Account passwords can be expired so that users must reset them. See Section 6.2.15, “Password Management”, and Section 6.2.16, “Server Handling of Expired Passwords”.

The validate_password plugin can be used to enforce a policy on acceptable password. See Section 6.4.3, “The Password Validation Component”.

A user who has access to modify the plugin directory (the value of the plugin_dir system variable) or the my.cnf file that specifies the plugin directory location can replace plugins and modify the capabilities provided by plugins, including authentication plugins.

Files such as log files to which passwords might be written should be protected. See Section 6.1.2.3, “Passwords and Logging”.