Information
When configured to use SSL/TLS, MySQL relies on Secure Sockets Layer (SSL) key files, which are stored on the host's filesystem. These SSL key files are subject to the host's permissions and ownership structure.
Rationale:
Limiting the accessibility of these objects will protect the confidentiality, integrity, and availability of the MySQL database and the communication with the client.
If the contents of the SSL key file are known to an attacker, he or she might impersonate the server. This can be used for a man-in-the-middle attack.
Depending on the SSL cipher suite, the key might also be used to decipher previously captured network traffic.
Impact:
If the permissions or ownership for the SSL key file are configured incorrectly, this can cause SSL to be disabled when MySQL is restarted or can cause MySQL not to start at all.
If other applications are using the same key pair, then changing the permissions or ownership of the SSL key file will affect this application. If this were to occur a new key pair must be generated for MySQL.
Solution
Execute the following commands at a terminal prompt to remediate these settings using the Value from the audit procedure:
chown mysql:mysql <ssl_file>
chmod 400 <ssl_file>