I am unable to have boxes connect back to my machine in certain circumstances, which makes some boxes impossible to complete. For the example here, I am attempting the Responder box under tier 1 of starting point and I am running Parrot OS on bare metal. I am able to run/connect my starting point vpn and gain access to the box’s IP. I am able to ping the box and get a response, I am able run a successful nmap scan, I can curl the box’s html, etc. Later on, I am supposed to set up responder to listen on tun0 and then alter the url to connect back to my machine via my tun0 address with RFI (task 6/page 8 in the walkthrough). Eventually the page times out and I receive the same error as shown in the walkthrough, but my responder never hears anything. Any thoughts on what might be happening? I can’t seem to find anyone else who has had this particular problem…
This also occurs on all other boxes where I have to RCE curl/wget back to an http server set up on my machine or if I am trying to use netcat instead of responder in similar situations. Basically my machine and the box are able to communicate unless I am attempting to reach my machine from the box.