Firefox listens on UDP *:35035
When using TBB (tor-browser-gnu-linux-x86_64-1.0.17-dev-en-US.tar.gz) on Ubuntu Maverick, I find that my computer is now listening on a number of TCP and UDP ports. I am running as a bridge and so I expect Tor to listen - it does. However, I was surprised to see the following entries for Firefox when I ran 'lsof -ni' as root:
firefox 2851 anon 34u IPv4 24118 0t0 UDP *:35035 run-mozil 2856 anon 34u IPv4 24118 0t0 UDP *:35035 firefox-b 2860 anon 34u IPv4 24118 0t0 UDP *:35035
My normal Ubuntu Firefox does not do this - why does the TBB Firefox bind to those UDP sockets?
I appear to be able send data with netcat over the network to those UDP ports. Additionally, the port numbers appear to be static as they appear to be the same when I re-launch TBB.
Why does the TBB Firefox do this? Why does it bind to all interfaces? What is the purpose and what is the risk?
Is it safe to use the TBB?