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Pivot & Tunnel

Host -> EC 2 Instance -> VDI -> Target Domain

Socks 5

  1. Start Chisel on the EC2 instance in server mode 
    sudo ./chisel_1.7.7_linux_amd64 server -p 8000 --reverse --socks5
  2. Start chisel in client mode in the VDI machine 
    ./chisel_1.7.7_linux_amd64  client <ec2_instance_ip>:8000 'R:socks'
  3. Port forward local port 9001 on your host to port 1080 on the EC2 instance >host : 9001 --> ec2 : 1080

N.B. I am not sure if administrator privelleges are required. 

ssh -L 9001:127.0.0.1:1080 admin@<ec2_ip> -N
4. Configure burp suite to use a socks proxy on your host

Port forwarding

  1. Install SSH Client on the VDI windows machine with the required capabilities.
Get-WindowsCapability -name openssh.client* -online | Add-WindowsCapability –Online

  1. Permit low privelleged users to bind to lower range ports (1-1024) on the EC2 instance. The admin user which is not root on the ec2 instance won't have the permission to bind to port 443 when remote port forwarding later on in this tutorial. 

    sudo sysctl net.ipv4.ip_unprivileged_port_start=443

  2. Modify the /etc/sshd/sshd_config on the EC2 instance to keep connections alive regardless of how inactive they are. uncomment the following in the sshd_config file.

# TCPKeepAlive yes
  1. Add host file entries that map the target domain to 127.0.0.1 to:
    1. EC 2 Instance host file
    2. Host hosts file

Example host file

127.0.0.1 localhost
127.0.0.1 <target_domain>
  1. Set up a remote port forward to port 443 on the EC 2 instance from the VDI machine

    ec2 :443 --> target:443

ssh -R 443:<target_domain> admin@<ec2_ip>
  1. Set up a Local port forward from the host to the ec2 instance

    host : 443 --> ec2 : 443 

ssh -L 443:127.0.0.1:443 admin@<ec2_ip>

NAT to NAT

TBD, I have not tested this yet.

Wireguard

NAT-to-NAT VPN with WireGuard

Tailscale

Tailscale is a modern VPN built on top of Wireguard. It works like an overlay network between the computers of your networks - using NAT traversal.

Everything in Tailscale is Open Source, except the GUI clients for proprietary OS (Windows and macOS/iOS), and the control server.

The control server works as an exchange point of Wireguard public keys for the nodes in the Tailscale network. It assigns the IP addresses of the clients, creates the boundaries between each user, enables sharing machines between users, and exposes the advertised routes of your nodes.

A Tailscale network (tailnet) is private network which Tailscale assigns to a user in terms of private users or an organisation.

Headscale

headscale aims to implement a self-hosted, open source alternative to the Tailscale control server. headscale has a narrower scope and an instance of headscale implements a single Tailnet, which is typically what a single organisation, or home/personal setup would use.

headscale uses terms that maps to Tailscale's control server, consult the glossary for explainations.

References

Allow non-root process to bind to port 80 and 443? Windows - Port forwarding using SSH How to use Windows 10/11 SOCKS5 Proxy Settings SSH Socks and Burp

SShuttle

To use sshuttle with JumpHost make sure the ~/.ssh/config is configured correctly. Checkout [[Infrastructure Pen test/SSH (22)#Config File Sample for jumphost]] 

# sshuttle
sudo sshuttle -v -r ubuntu 10.1.4.0/24

Misc

General-purpose bash snippets

# Kill process listenting on port 443
kill -9 $(sudo netstat -alpn | grep 443 | grep LISTEN | grep -v tcp6 | grep -oP '[0-9]{4,}')