Moodle versions 2.7 and earlier suffer from a vulnerability that discloses the account name for a specified profile ID.
3e167578263db5e084328661c2ca6f40https://www.osisecurity.com.au/moodle-url-manipulation-remote-account-information-disclosure.html
Date:
04-Apr-2017
Product:
Moodle
Versions affected:
2.4.10, 2.5.6, 2.6.3, 2.7 and earlier.
Vulnerability:
Information disclosure.
Example:
/user/edit.php?id= reveals account owner name
1. Log in to http://demo.moodle.net/ as user student:sandbox.
2. Click view profile when logged in (student is id=4).
3. Change id parameter from 4 to 3, which is the teacher
(http://demo.moodle.net/user/profile.php?id=3). The HTML response says
'Terri Teacher' who the 'student' user has access to.
4. Change id parameter to 2
(http://demo.moodle.net/user/profile.php?id=2). The HTML response says
"The details of this user are not available to you" and the navigation
bar above says "Home / My profile / View profile / User".
5. Note that it says "User" - but hides the name!
6. Change the URL from profile.php to edit.php
(http://demo.moodle.net/user/edit.php?id=2).
7. The HTML message is "Sorry, but you do not currently have
permissions to do that (Edit user profile)" ... BUT, the navigation
bar says "Home / Users / Admin User".
VoilA ! The account name is "Admin User"
Effective on university websites which have 1+ million end users.
Credit:
Discovered by Patrick Webster
Disclosure timeline:
29-May-2014 - Discovered during audit, reported to tracker.
11-Jul-2014 - Fix committed MDL-45760.
14-Jul-2014 - Patch released for 2.4.11, 2.5.7, 2.6.4, 2.7.1.
04-Apr-2017 - Public disclosure.
About OSI Security:
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