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Bekijk Volledige Versie : Multiple Vulnerabilities in Moodle



Bartek Nowotarski
28/12/04, 18:25
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| Multiple Vulnerabilities in Moodle |
| ================================== |
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| Author: Bartek Nowotarski |
| Published: 2004-12-27 |
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[01] General information
~~~~~~~~~~~~~~~~~~~~~~~~

] Document author: Bartek Nowotarski (silence) [
] Location: Trzebinia, Poland [
] E-mail: silence10 wp pl [
] Site: silence 0 pl [

] Application: Moodle [
] Versions vulnerable: <= 1.4.2 [


[02] Introduction
~~~~~~~~~~~~~~~~~

`Moodle is a course management system (CMS) - a software package designed to
help educators create quality online courses. Such e-learning systems are
sometimes also called Learning Management Systems (LMS) or Virtual Learning
Environments (VLE).` /www.moodle.org
It has over 1000 *register* sites in 75 countries.

Project home site: http://www.moodle.org


[03] Vulnerabilities
~~~~~~~~~~~~~~~~~~~~

Two vulnerabilities have been found in Moodle CMS:

a) ] Type: Cross Site Scripting [
] File: /mod/forum/view.php [

] Description: [

It is a well-known fact that all user-dependant variables should be
checked for inaccurate values. The variable $search in view.php is
not.

54> $buttontext = forum_print_search_form($course, $search, true,
> "plain");

] Proof of concept: [

The following request will alert values of logged user cookies:

> http://localhost/moodle/mod/forum/view.php?id=1&search=moodle%22%3E
> %3Cscript%3Ealert(document.cookie)%3C/script%3E

Where id variable should be existing course ID.

b) ] Type: Session File Disclosure [
] File: file.php [

] Description: [

All files containing session data are saved in `moodledata` dir, which
should be invisible from web. But it is possible to gain access to them:

45> $pathname = "$CFG->dataroot$pathinfo";

$pathinfo is checked by function detect_munged_arguments() and allows
one use of `..` to skip to parent directory. We can use it to skip to
`moodledata` folder itself and then read files form `sess`.
To obtain session ID we can use cross site scripting vulnerability.

] Proof od concept: [

The following request will disclosure session file:

> http://localhost/moodle/file.php?file=/1/../sessions/
> sess_6ac3b47ee23c6aa55896f4cd68af9622

Where:
- `1` after "?file=/" is existing course ID,
- `6ac3b47ee23c6aa55896f4cd68af9622` is session ID


[04] Solution
~~~~~~~~~~~~~

Session File Disclosure vulnerability is patched in version 1.4.3.
Cross Site Scripting vulnerability will be patched probably in
version 1.5.


[05] Timeline
~~~~~~~~~~~~~

] 2004-12-09 [ Session File Disclosure vulnerability (b) discovered
] 2004-12-10 [ Cross Site Scripting vulnerability (a) discovered
] 2004-12-13 [ Vendor informed
] 2004-12-14 [ Session File Disclosure vulnerability (b) patched
] 2004-12-27 [ Advisory published


[06] Credits
~~~~~~~~~~~~

Vulnerabilities discovered by Bartek Nowotarski.


--EOF--

Martin Dougiamas
31/12/04, 00:05
In-Reply-To: <20041227194544.6255.qmail@www.securityfocus.com>


>Session File Disclosure vulnerability is patched in version 1.4.3.
>Cross Site Scripting vulnerability will be patched probably in
>version 1.5.

In fact both of these were fixed in 1.4.3 (the currently available release).