The best place to start is Chapter 8, Security.

Other portions of the MySQL Documentation which you may find useful with regard to specific security concerns include the following:

There is also the Secure Deployment Guide, which provides procedures for deploying a generic binary distribution of MySQL Enterprise Edition Server with features for managing the security of your MySQL installation.

The default authentication plugin as of MySQL 8.0 is caching_sha2_password. For information about this plugin, see Section 8.4.1.2, “Caching SHA-2 Pluggable Authentication”.

The caching_sha2_password plugin provides more secure password encryption than the deprecated mysql_native_password plugin (the default plugin in MySQL versions before MySQL 8.0). For information about the implications of this change of default plugin for server operation and compatibility of the server with clients and connectors, see caching_sha2_password as the Preferred Authentication Plugin.

For general information about pluggable authentication and other available authentication plugins, see Section 8.2.17, “Pluggable Authentication”, and Section 8.4.1, “Authentication Plugins”.

Yes, the binaries have support for SSL connections between the client and server. See Section 8.3, “Using Encrypted Connections”.

You can also tunnel a connection using SSH, if (for example) the client application does not support SSL connections. For an example, see Section 8.3.4, “Connecting to MySQL Remotely from Windows with SSH”.

Yes, the binaries have SSL enabled for client/server connections that are secured, authenticated, or both. See Section 8.3, “Using Encrypted Connections”.

The Enterprise edition includes a PAM Authentication Plugin that supports authentication against an LDAP directory.

Not at this time.

Support for the TLSv1 and TLSv1.1 connection protocols is removed as of MySQL 8.0.28. The protocols were deprecated from MySQL 8.0.26. For the consequences of that removal, see Removal of Support for the TLSv1 and TLSv1.1 Protocols.

Support for TLS versions 1.0 and 1.1 is removed because those protocol versions are old, released in 1996 and 2006, respectively. The algorithms used are weak and outdated.

Unless you are using very old versions of MySQL Server or connectors, you are unlikely to have connections using TLS 1.0 or 1.1. MySQL connectors and clients select the highest TLS version available by default.

When was support for TLS 1.2 added to MySQL Server? MySQL Community Server added TLS 1.2 support when the community server switched to OpenSSL for MySQL 5.6, 5.7, and 8.0 in 2019. For MySQL Enterprise Edition, OpenSSL added TLS 1.2 support in 2015, in MySQL Server 5.7.10.

How can one view which TLS versions are in active use? For MySQL 5.7 or 8.0, review whether TLS 1.0 or 1.1 is in use by running this query:

SELECT
  `session_ssl_status`.`thread_id`, `session_ssl_status`.`ssl_version`,
  `session_ssl_status`.`ssl_cipher`, `session_ssl_status`.`ssl_sessions_reused`
FROM `sys`.`session_ssl_status` 
WHERE ssl_version NOT IN ('TLSv1.3','TLSv1.2');

If a thread using TLSv1.0 or TLSv1.1 is listed, you can determine where this connection is coming from by running this query:

SELECT thd_id,conn_id, user, db, current_statement, program_name 
FROM sys.processlist
WHERE thd_id IN (
                  SELECT `session_ssl_status`.`thread_id`
                  FROM `sys`.`session_ssl_status` 
                  WHERE ssl_version NOT IN ('TLSv1.3','TLSv1.2')
                );

Alternatively, you can run this query:

SELECT * 
FROM sys.session 
WHERE thd_id IN (
                  SELECT `session_ssl_status`.`thread_id`
                  FROM `sys`.`session_ssl_status` 
                  WHERE ssl_version NOT IN ('TLSv1.3','TLSv1.2')
                );

These queries provide details needed to determine which application is not supporting TLS 1.2 or 1.3, and target upgrades for those.

Are there other options for testing for TLS 1.0 or 1.1? Yes, you can disable those versions prior to upgrading your server to a newer version. Explicitly specify which version to use, either in mysql.cnf (or mysql.ini) or by using SET PERSIST, for example: --tls-version=TLSv12.

Do all MySQL Connectors (5.7 and 8.0) support TLS 1.2 and higher? What about C and C++ applications using libmysql? For C and C++ applications using the community libmysqlclient library, use an OpenSSL-based library (that is, do not use YaSSL). Usage of OpenSSL was unified in 2018 (in MySQL 8.0.4 and 5.7.28, respectively). The same applies for Connector/ODBC and Connector/C++. To determine what library dependencies are used, run the following commands to see if OpenSSL is listed. On Linux, use this command:

$> sudo ldd usr/local/mysql/lib/libmysqlclient.a | grep -i openssl

On MacOS, use this command:

$> sudo otool -l /usr/local/mysql/lib/libmysqlclient.a | grep -i openssl

Check the documentation for each connector, but they do support TLS 1.2 and TLS 1.3.