MySQL 8.0 Reference Manual Including MySQL NDB Cluster 8.0 End-User Guidelines for Password Security

MySQL users should use the following guidelines to keep passwords secure.

When you run a client program to connect to the MySQL server, it is inadvisable to specify your password in a way that exposes it to discovery by other users. The methods you can use to specify your password when you run client programs are listed here, along with an assessment of the risks of each method. In short, the safest methods are to have the client program prompt for the password or to specify the password in a properly protected option file.

On Unix, the mysql client writes a record of executed statements to a history file (see Section, “mysql Client Logging”). By default, this file is named .mysql_history and is created in your home directory. Passwords can be written as plain text in SQL statements such as CREATE USER and ALTER USER, so if you use these statements, they are logged in the history file. To keep this file safe, use a restrictive access mode, the same way as described earlier for the .my.cnf file.

If your command interpreter maintains a history, any file in which the commands are saved contains MySQL passwords entered on the command line. For example, bash uses ~/.bash_history. Any such file should have a restrictive access mode.