Cyber Anakins Lightsaber - A Minishell-based backdoor

<?php

session_start();
if (!isset($_SESSION['protectCode'])) die('no session');
$code = $_SESSION['protectCode'];
$code = "$code";


$image = imagecreatetruecolor(80,30);

$color = imagecolorallocate($image, 0x33, 0x33, 0x33);
imagefilledrectangle($image, 0, 0, 80, 30, $color);

for($i=0; $i < 20;$i++)
{
	$color = imagecolorallocate($image, 0x77+rand(-30,30), 0x77+rand(-30,30), 0x77+rand(-30,30));
	imageline($image,0,rand(0,30),80,rand(0,30),$color);
}



$L = strlen($code);
$x = 10;
for($i=0; $i<$L; $i++, $x+=15)
{
	$c = $code{$i};

	$color = imagecolorallocate($image, 0xcc+rand(-40,40), 0xcc+rand(-40,40), 0xcc+rand(-40,40));
	imagestring($image, 5, $x + rand(-5,5), rand(2,14), $c, $color);
}

header("Content-Type: image/gif");
imagegif($image);
imagedestroy($image);

?>