You should verify that the TLS CA certificate file, the file that is passed along with the
--tlscacert parameter, is individually owned and group owned by root.
The TLS CA certificate file should be protected from any tampering. It is used to authenticate the Docker server based on a given CA certificate. It must be therefore be individually owned and group owned by root to ensure that it cannot be modified by less privileged users.
You should execute the command below to verify that the TLS CA certificate file is owned and group owned by root:
stat -c %U:%G <path to TLS CA certificate file> | grep -v root:root
This command does not return any data.
Run the following command:
chown root:root <path to TLS CA certificate file>
This sets the individual ownership and group ownership for the TLS CA certificate file to root.
By default, the ownership and group-ownership for TLS CA certificate file is correctly set to root.
5.1 Minimize And Sparingly Use Administrative Privileges - Minimize administrative privileges and only use administrative accounts when they are required. Implement focused auditing on the use of administrative privileged functions and monitor for anomalous behavior.