Cyber Anakins Lightsaber - A Minishell-based backdoor

<?php

require("std2.php");
require("paymentutils.php");


function ErrLog($txt)
{
	$f = fopen("_robokassa_error.txt","w");
	fprintf($f, $txt);
	fclose($f);
	die($txt);
}

if (!isset($_REQUEST['OutSum']))
{
	ErrLog("ERROR: No OutSum");
	die("ERROR: No OutSum");
}

if (!isset($_REQUEST['InvId']))
{
	ErrLog("ERROR: No InvId");
	die("ERROR: No InvId");
}

if (!isset($_REQUEST['SignatureValue']))
{
	ErrLog("ERROR: No SignatureValue");
	die("ERROR: No SignatureValue");
}

// HTTP parameters:
$out_summ = $_REQUEST["OutSum"];
$inv_id = $_REQUEST["InvId"];
$crc = $_REQUEST["SignatureValue"];

$crc = strtoupper($crc);  // force uppercase

$mrh_pass2 = mrh_pass2;

// build own CRC
$my_crc = strtoupper(md5("$out_summ:$inv_id:$mrh_pass2"));

//*
if ($my_crc!=$crc)
{
	ErrLog("ERROR: Invalid SignatureValue: $crc mycrc $my_crc (InvID:$inv_id)");
	die("ERROR: Invalid SignatureValue");
}
//*/



$mysql = mysqlopen();

$order = $inv_id;

mysqli_query($mysql,"UPDATE libOrders SET `payDate`=NOW() WHERE `id`=$order");
if (mysqli_errno($mysql)) ErrLog("mysql error: ".mysqli_error($mysql));

die("OK");

?>