Whenever I have the Flash Player.plugin in the Libraries/Internet Plugins folder on my iMac, this shows in the privacy->cookies/plugins
I narrowed it down to flash by moving all plugins out of that folder and restoring them one at a time. Once I narrowed it down to flash, I deleted the Adobe Flash folder and the re-installed Flash from a current download at get.adobe.com.
As soon as I restart Safari, that IP address is back. As soon as I remove the Flash Player.plugin from the folder, it goes away.