ValueError when connecting via loopback

Bug Description

This is normally only a testing problem, as practically, you aren’t often connecting to localhost. That being said, when connecting to a bind shell on the local machine, pwncat is unable to use localhost. Getting the peer name from the socket apparently results in a different return value for the loopback device vice a normal IP address.

You can use 127.0.0.1, and it works just fine. This should be relatively easy to test/fix. I just need to figure out what exactly the expected return value is for a loopback device.

pwncat version

Provide the output of pwncat --version or a commit hash if working from a development branch.

$ pwncat --version
0.4.3

Target System (aka “victim”)

My local machine, which is an Arch Linux host.

Steps to Reproduce

Steps to reproduce the behavior:

1. Start a listener with ncat -e /bin/bash -klnvp 4444
2. Attempt to connect to the listener with pwncat localhost 4444
3. See error

Expected Behavior

A connection is established in the same way as using 127.0.0.1 in place of localhost.

[Mitul16]

I have seen this before. This happens when we create the bind shell using IPv6 protocol or AF_INET6 address family And thus we do not get (host, port) pair tuple as the return value which is what pwncat expects.

[Mitul16]

I did thought about fixing it 😁 , but I thought who is using IPv6 anyway. And the current implementation for parsing the host and port using an IPv6 address will throw an error as well.