You will notice on a Ubuntu system when you give the following command in a terminal window,
sudo netstat -tpW <enter>
it shows many open connections which do not get closed. These will have the process gvfsd-http listed against them.
To close these connections, you can kill the gvfsd-http process and also remove rhythmbox entirely.
sudo apt-get remove rhythmbox-data librhythmbox-core5 <enter>
Then reboot. If you still find gvfsd-http in your processes list, you can kill it. Although not a security threat, it is definitely a nuisance.