> We just heard a rumor about our rival company, that they have developed > a "system" that can completely bypass a properly-configured/locked-down > firewall (netfilter or any other). > > Is this truly possible? with only external access and no software that's > already been planted inside the firewall? > If you have someone at the "inside" there is no problem to create tunnels with for example OpenVPN that completly "bypasses" the firewall. If you create a tunnel with OpenVPN over https and bridge the networks together you could get everything through with the traffic looking just like ordinary https-traffic. But with only access from the outside it is very vary hard, if not impossible. // Jimmy
