[MajorSecurity Advisory #54]xt:Commerce - Cross Site Scripting and Session Fixation Issues
[MajorSecurity Advisory #54]xt:Commerce - Cross Site Scripting and Session
Fixation Issues
Details
=======
Product: xt:Commerce
Security-Risk: moderated
Remote-Exploit: yes
Vendor-URL: http://www.xtcommerce-shop.com/
Vendor-Status: informed
Advisory-Status: published
Credits
============
Discovered by: David Vieira-Kurz
http://www.majorsecurity.de
Affected Products:
----------------------------
xt:Commerce 3.04 and prior
Original Advisory:
============
http://www.majorsecurity.de/index_2.php?major_rls=major_rls54
Introduction
============
xt:Commerce is one of the leading webshop systems based on the eCommerce Engine.
More Details
============
1. Cross Site Scripting:
----------------------
1.1 Input passed directly to the "keywords" parameter in
"advanced_search_result.php" is not properly sanitised before being returned to
the user.
This can be exploited to execute arbitrary HTML and script code in a user's
browser session in context of an affected site.
1.2 PoC:
============
/advanced_search_result.php?keywords=/>"<script>alert(15)</script>&x=1&y=1
1.3 Workaround
=============
Edit the source code to ensure that input is properly sanitised.
You should work with "htmlspecialchars()" or "htmlentities()" php-function to
ensure that html tags
and javascript code are not going to be executed.
Example:
$keywords = htmlentities($_POST['keywords']);
$keywords = htmlspecialchars($_GET('keywords'));
?>
2. session fixation:
---------------------
The "PHPSESSID" parameter can be set to a malicious and arbitrary value.
2.1 Description:
In a session fixation attack, the attacker fixes the user's session ID before
the user even logs into the target server.
After a user's session ID has been fixed, the attacker will wait for them to
login.
Once the user does so, the attacker uses the predefined session ID value to
assume their online identity.
2.2 PoC:
============
https://localhost/xtcommerce304/shopping_cart.php/XTCsid/15031988
2.3 Workaround:
============
1. Do not accept session identifiers from GET / POST variables.
2.Regenerate SID on each request.
3. Accept only server generated SID:
One way to improve security is to not accept session identifiers not generated
by server.
if ( !isset( $_SESSION['SERVER_GENERATED_SID'] ) ) {
session_destroy(); // destroy all data in session
}
session_regenerate_id(); // generate a new session identifier
$_SESSION['SERVER_GENERATED_SID'] = true;
Solution
=============
Edit the source code to ensure that input is properly sanitised.
You should work with "htmlspecialchars()" or "htmlentities()" php-function to
ensure that html tags
and javascript code are not going to be executed.
Example:
$password = htmlentities($_POST['pass']);
$search = htmlspecialchars($_GET['search']);
?>
MajorSecurity
================
MajorSecurity is a German penetrationtesting and security research company
which focuses
on web application security. We offer professional penetrationtestings and
reliable proof
of concepts.
You will find more Information about MajorSecurity at
http://www.majorsecurity.de/