Comodo, GRC & VPN Connections

Hi All,

I’m using Comodo firewall (French version) and while I have been an happy user so far, I am experiencing unsatisfying results while leading shields up tests at grc.com with a VPN connection.

Indeed, if all my ports appear to be stealth when I don’t use any VPN, if I use a VPN either PPTP or OpenVPN, many ports appear open or closed but very few are stealth. In details, using PPTP connection, with “file sharing” test my computer and network names are visible, and in “common ports” test my ports 135, 139 & 445 appear open. Using OpenVPN instead, my computer and network names aren’t visible anymore, but in common ports, many are open or closed, very few being stealth.

Can you help me? How to configure Comodo so while using VPN connections my computer appears as safe as when not using them?

Thank you.

If your using VPN your probably scanning the VPN endpoint, and not your real system.

I assume these VPN’s don’t give you an exclusive public IP address but an “internal” IP to go to the central equipment, and there you get translated to the public IP of the service, that’s the IP that get’s scanned.

I highly doubt that the scan requests reach your system if you do a GRC on the VPN connections.

Can you verify if the IP’s you get on the tunnels are in the private range?
10.x.y.z.
172.16 - 172.31
192.168.x.y

Hi Ronny, thank you for your answer.

At first, I thought you were probably right. And as a matter of fact, I checked both VPN connections, PPTP and OpenVPN, IP address tested at grc.com with ShieldUP is my public IP provided by the VPN service, not one of the IPs I get on the tunnel (which are included in the mentionned private range). Now, when using PPTP, as mentionned earlier, ShieldsUP, during “file sharing” test, really reaches my computer since it displays both name of that machine and the network it belongs to… Ports 135 ,139 & 445 are opened and seem to be open for everybody to access. That is certainly wrong, and while it doesn’t happen with OpenVPN, I certainly would like to fix that. How can I?

Thank you,

Looks like the firewall driver is missing the PPTP interface.

Can you post a screenshot of the adapters (network properties) and can you also verify if it has the Comodo Firewall Driver attached to the interface like the normal interface has also?

Hi again Ronny,

I am not quite sure how I can make screeenshots (but should find out if necessary) neither what you exactly want to see. Do you mean that when I’m looking at network management tab of my VPN PPTP adapters, I should see Comodo Internet Security Firewall Driver as I can see it in network management tab for local controller? If answer is yes, well that may be the problem as I don’t see the driver in VPN PPTP Adapter network management tab. I have tried to install it manually, but it doesn’t seem to work… I don’t have any clue here…

Thank you,

Hi I verified, this should work, maybe a bug.

Can you export the config, uninstall CIS and re-install CIS and import you config again to verify it the driver get’s installed (possibly the PPTP interface was created after CIS install?).