How to use proxy service on pfsense to block team viewer

asankaj2006 · Nov 15, 2011, 7:37 AM

Dear All

I need to restrict team viewer using pfsense.

can some help me with this.

Thanks.
Asanka

hugo · Nov 15, 2011, 1:36 PM

I believe that TeamViewer is a VNC derivative. Try blocking 5900

Metu69salemi · Nov 15, 2011, 2:01 PM

@http://www.teamviewer.com/fi/kb/10-Which-ports-does-TeamViewer-use.aspx:

Which ports does TeamViewer use?

By default TeamViewer uses only the outgoing port 80 (HTTP) - no firewall configuration is necessary. Alternatively you can open port 5938 (TCP) for outgoing connections.

Only thing is anymore, that you sniff where teamviewer takes connections with port 80 and block that ip

johnpoz · Nov 15, 2011, 2:26 PM

I would have to do a sniff, but from my understanding it runs on 80 and 443 but does not use the http or https protocol - so you should be able to use a layer 7 filter to block that traffic?

Just did a quick sniff of running it and it only used port 5938 outbound.. Could block that to see how it tries if that port is blocked.

For dns it used ping3.teamviewer.com and master12.teamviewer.com, I would think simple way to prevent access might to just create dns for the teamviewer.com domain and send bad info ;)

Ok just blocked 5938 and it went out on 443, this time to master5.teamviewer.com but it was not HTTPS..