> For the complete documentation index, see [llms.txt](https://mariadb.com/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://mariadb.com/docs/server/reference/plugins/authentication-plugins/authentication-plugin-mysql_old_password.md).

# Authentication Plugin - mysql\_old\_password

This plugin provides backward compatibility for pre-4.1 clients using an older, insecure password hashing algorithm and should not be used for new installations.