When you're connected to an anonymization server of the CyberGhost network, a new IP address will be assigned to you with which you are accessing the Internet from then on until you disconnect. That way your original IP gets hidden, while all Internet activities will be mediated through the CyberGhost IP address.
Did you, however, in the time between system startup and connection to the CyberGhost network log in a user account and got your original IP noted (or on a different occasion), this information can be misused by hackers to attack this address directly from the Internet. This is because your old IP address is still valid; it has been assigned to your physical connection from your ISP and therefore is still 'on the Internet available', even if it is not actively used by you. But directly addressed, DDoS attacks are possible as are, less dramatic, 'out-lagging activities' when playing online games.
If you don't want your original IP leaked before CyberGhost steps in, please start CyberGhost with system start and let it connect to a server immediately.