Sorry to hear that. That directory has nothing to do with Community Builder.
For advice helping restore and increasing security, please see here:
help.joomla.org/component/option,com_easyfaq/task,cat/catid,226/Itemid,268/
Particularly the "Recover" section, and vulnerable extensions list.
Wishing you good luck getting back online. Nothing fun to handle, but often lots to learn too in the process...