Exploit-DB #48348
Description: Fork CMS 5.8.0 - Persistent Cross-Site Scripting
Type: webapps
Platform: php
Date: 2020-04-20
Author: Vulnerability-Lab

Exploit:
# Title: Fork CMS 5.8.0 - Persistent Cross-Site Scripting
# Author: Vulnerability Laboratory
# Date: 2020-04-15
# Vendor: https://www.fork-cms.com/download
# Software Link: https://github.com/forkcms/forkcms/pull/3073
# CVE: N/A

Document Title:
===============
Fork CMS v5.8.0 - Multiple Persistent Web Vulnerbilities


References (Source):
====================
https://www.vulnerability-lab.com/get_content.php?id=2208

ID (3073):  https://github.com/forkcms/forkcms/pull/3073


Release Date:
=============
2020-04-17


Vulnerability Laboratory ID (VL-ID):
====================================
2208


Common Vulnerability Scoring System:
====================================
5.3


Vulnerability Class:
====================
Cross Site Scripting - Persistent


Current Estimated Price:
========================
1.000€ - 2.000€


Product & Service Introduction:
===============================
Fork is an easy to use open source CMS using Symfony Components. Fork
CMS is dedicated to creating a user friendly environment
to build, monitor and
update your website. We take great pride in being the Content Management
System of choice for beginners and professionals.

(Copy of the Homepage: https://www.fork-cms.com  &
https://www.fork-cms.com/download )


Abstract Advisory Information:
==============================
The vulnerability laboratory core research team discovered multiple
persistent web vulnerabilities in the official Fork CMS v5.8.0.


Affected Product(s):
====================
ForkCMS
Product: Fork CMS v5.8.0 - Content Management System (Web-Application)


Vulnerability Disclosure Timeline:
==================================
2020-04-17: Public Disclosure (Vulnerability Laboratory)


Discovery Status:
=================
Published


Exploitation Technique:
=======================
Remote


Severity Level:
===============
Medium


Authentication Type:
====================
Restricted authentication (user/moderator) - User privileges


User Interaction:
=================
Low User Interaction


Disclosure Type:
================
Independent Security Research


Technical Details & Description:
================================
Multiple persistent input validation web vulnerabilities has been
discovered in the official Fork CMS v5.8.0 open-source web-application.
The vulnerability allows remote attackers to inject own malicious script
codes with persistent attack vector to compromise browser to
web-application requests from the application-side.

The persistent input validation web vulnerabilities are located in the
`Displayname` input field when using the `Add`, `Edit` or `Register`
mechanism that forwards the information into the `var` parameter. Remote
attackers and privileged application user accounts are able to
inject own malicious persistent script code as the users displayname by
usage of the registration module (/profiles/register). Privileged
users with access to the profile or users module are able to exploit the
issue by a simple inject. The displayname then becomes visible in
the Admin - Profiles Index on Preview, Edit User/Profile, Delete User
Interaction and User Index in Listing modules. the var parameter
does not encode or parse the exisiting injected content and executes it.
The request method to inject is POST and the attack vector of the
vulnerability is located on the application-side of the content
management system. The injection point is located in the registration form
and the add/edit user function. The execution point of the issue occurs
in the preview profile, edit user, user index listing and delete
user message context.

Successful exploitation of the vulnerabilities results in session
hijacking, persistent phishing attacks, persistent external redirects to
malicious source and persistent manipulation of affected application
modules.

Request Method(s):
[+] POST

Vulnerable Module(s):
[+] Register
[+] Add User
[+] Edit User

Vulnerable Input(s):
[+] Displayname

Vulnerable Parameter(s):
[+] var

Affected Module(s):
[+] Preview Profile
[+] Edit User
[+] User Index
[+] Delete User


Proof of Concept (PoC):
=======================
The persistent input validation web vulnerabilities can be exploited by
remote attackers with low privileged user account and low user interaction.
For security demonstration or to reproduce the security vulnerability
follow the provided information an steüs below to continue.


Manual steps to reproduce the vulnerability ...
1. Open the fork cms web-application newst version
2. Move via sitemap or by link to the registration page
(/modules/profiles/register)
3. Inject your script code payload html/js to the Displayname input field
4. Register the account by pushing submit
5. Activate the link in the account registration email
Note: Now simple wait until the administrator / privileged user visits
the panel to execute the code on interaction or preview only
6. Successful reproduce of the persistent script code injection
vulnerability!


PoC: Vulnerable Source (User Index in Listing -
https://fork-cms.localhost:8080/private/en/users/index)
<tr id="row-2" class="even">
<td class="nickname"><a
href="/private/en/users/edit?token=k7byefqor8&id=2"
title="edit">test3"><iframe src="evil.source"
onload=alert(document.cookie)></a></td>
<td  class="fork-data-grid-action actionEdit"><a
href="/private/en/users/edit?token=k7byefqor8&id=2"
class="btn btn-default btn-xs pull-right">
<span class="fa fa-pencil" aria-hidden="true"></span>&nbsp;Edit</a></td>
</tr>


PoC: Vulnerable Source (Profiles Index on Preview -
https://fork-cms.localhost:8080/private/en/profiles/index)
<tbody><tr id="row-1" class="odd">
<td class="check"><input type="checkbox" name="id[]" value="1"
class="inputCheckbox checkBeforeUnload"></td>
<td class="email"><a
href="/private/en/profiles/edit?token=k7byefqor