Bridging the WiFi and Ethernet network for a remote shell to an air-gapped PC

[legrandale]

I am not sure if I am just blind or it's a problem that only involves me. But my aim was to have the RPIZ act as a router, that when plugged in on the targetted machine via usbeth, it allows an attacking machine that is connected to the RPIZ via Wifi to communicate with the former network directly. This means that I can ping the machines, and ultimately have an access to the air-gapped PC through a meterpreter session created from a reverse shell.

The problem is that the networks are not bridged, so I cannot communicate between the machines.

I was trying to set up a bridge via SSH using iptables commands :

sudo iptables -t nat -A POSTROUTING -o wlan0 -j MASQUERADE

But the command would take an eternity to execute. I had to manually interrupt it with CTRL+C.

I tried messing around with iptables to see if it was an outdated version (which it seems to be) and update it but ended up breaking it.

I didn't see an alternative on the Web interface , nor any tutorial that was explicit concerning my problem.