There are few tips here which will help you protect your vps against attacks:
1. Change SSH port :
you can change it be logging into you server console with root privilages.
Then type
# vi /etc/ssh/sshd_config
and find line #22 and replace it with the port you want to be a ssh port
Now restart server by typing
reboot
2. Change phpmyadmin default url . You can do it in apache configuration file folder. In centos 7 with vesta cp installed the file is located in
/etc/httpd/conf.d/phpMyAdmin.conf
edit it with command
vi /etc/httpd/conf.d/phpMyAdmin.conf
and change Alias line
3. Keep On changing your account password with
passwd
Command in the interval of few months