Moodle Cross-site Scripting

A reflected cross-site scripting vulnerability was discovered in Moodle. This flaw exists due to insufficient sanitization of user-supplied data in policy tool. An attacker can trick the victim to open a specially crafted link that executes an arbitrary HTML and script code in user's browser in context of vulnerable website. This vulnerability may allow an attacker to perform cross-site scripting (XSS) attacks to gain access potentially sensitive information and modification of web pages. (2022-11-23, CVE-2022-45150)

The stored-XSS vulnerability was discovered in Moodle which exists due to insufficient sanitization of user-supplied data in several "social" user profile fields. An attacker could inject and execute arbitrary HTML and script code in user's browser in context of vulnerable website. (2022-11-23, CVE-2022-45151)

Recursive rendering of Mustache template helpers containing user input could, in some cases, result in an XSS risk or a page failing to load. (2022-09-30, CVE-2022-40313)

In certain Moodle products after creating a course, it is possible to add in a arbitrary "Topic" a resource, in this case a "Database" with the type "Text" where its values "Field name" and "Field description" are vulnerable to Cross Site Scripting Stored(XSS). This affects Moodle 3.11 and Moodle 3.10.4 and Moodle 3.9.7. (2022-09-13, CVE-2021-36568)

In Moodle before 3.9.1, 3.8.4 and 3.7.7, the filter in the admin task log required extra sanitizing to prevent a reflected XSS risk. (2022-08-16, CVE-2020-14320)

In Moodle 3.8, messages required extra sanitizing before updating the conversation overview, to prevent the risk of stored cross-site scripting. (2022-08-05, CVE-2020-1691)

A reflected XSS issue was identified in the LTI module of Moodle. The vulnerability exists due to insufficient sanitization of user-supplied data in the LTI module. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website to steal potentially sensitive information, change appearance of the web page, can perform phishing and drive-by-download attacks. This vulnerability does not impact authenticated users. (2022-07-25, CVE-2022-35653)

A stored XSS and blind SSRF vulnerability was found in Moodle, occurs due to insufficient sanitization of user-supplied data in the SCORM track details. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website to steal potentially sensitive information, change appearance of the web page, can perform phishing and drive-by-download attacks. (2022-07-25, CVE-2022-35651)

A flaw was found in moodle where ID numbers displayed when bulk allocating markers to assignments required additional sanitizing to prevent a stored XSS risk. (2022-05-18, CVE-2022-30596)

ID numbers displayed in the quiz grading report required additional sanitizing to prevent a stored XSS risk. Moodle 3.10 to 3.10.3, 3.9 to 3.9.6, 3.8 to 3.8.8, 3.5 to 3.5.17 and earlier unsupported versions are affected. (2022-03-11, CVE-2021-32475)

The redirect URI in the LTI authorization endpoint required extra sanitizing to prevent reflected XSS and open redirect risks. Moodle versions 3.10 to 3.10.3, 3.9 to 3.9.6, 3.8 to 3.8.8 and earlier unsupported versions are affected. (2022-03-11, CVE-2021-32478)

A flaw was found in Moodle in versions 3.11 to 3.11.3, 3.10 to 3.10.7, 3.9 to 3.9.10 and earlier unsupported versions. A URL parameter in the filetype site administrator tool required extra sanitizing to prevent a reflected XSS risk. (2021-11-22, CVE-2021-43558)

Cross Site Scripting (XSS) in Moodle 3.10.3 allows remote attackers to execute arbitrary web script or HTML via the "Description" field. (2021-06-16, CVE-2021-32244)

Text-based feedback answers required additional sanitizing to prevent stored XSS and blind SSRF risks in moodle before 3.10.2, 3.9.5, 3.8.8, 3.5.17. (2021-03-15, CVE-2021-20280)

The ID number user profile field required additional sanitizing to prevent a stored XSS risk in moodle before 3.10.2, 3.9.5, 3.8.8, 3.5.17. (2021-03-15, CVE-2021-20279)

It was found in Moodle before version 3.10.1 that some search inputs were vulnerable to reflected XSS due to insufficient escaping of search queries. (2021-01-28, CVE-2021-20183)

It was found in Moodle before version 3.10.1, 3.9.4, 3.8.7 and 3.5.16 that if the TeX notation filter was enabled, additional sanitizing of TeX content was required to prevent the risk of stored XSS. (2021-01-28, CVE-2021-20186)

The moodlenetprofile user profile field required extra sanitizing to prevent a stored XSS risk. This affects versions 3.9 to 3.9.1. Fixed in 3.9.2. (2020-12-09, CVE-2020-25627)

A vulnerability was found in Moodle 3.9 to 3.9.1, 3.8 to 3.8.4 and 3.7 to 3.7.7 where it was possible to include JavaScript in a book's chapter title, which was not escaped on the "Add new chapter" page. This is fixed in 3.9.2, 3.8.5 and 3.7.8. (2020-12-08, CVE-2020-25631)

The filter in the tag manager required extra sanitizing to prevent a reflected XSS risk. This affects 3.9 to 3.9.1, 3.8 to 3.8.4, 3.7 to 3.7.7, 3.5 to 3.5.13 and earlier unsupported versions. Fixed in 3.9.2, 3.8.5, 3.7.8 and 3.5.14. (2020-12-08, CVE-2020-25628)

In Moodle, it was possible to include JavaScript when re-naming content bank items. Versions affected: 3.9 to 3.9.2. This is fixed in moodle 3.9.3 and 3.10. (2020-11-19, CVE-2020-25702)

A vulnerability was found in moodle 3.7 before 3.7.3, where there is blind XSS reflected in some locations where user email is displayed. (2020-03-18, CVE-2019-14881)

A vulnerability was found in Moodle 3.7 before 3.73, 3.6 before 3.6.7 and 3.5 before 3.5.9, where a reflected XSS possible from some fatal error messages. (2020-03-18, CVE-2019-14884)

Persistent XSS in /course/modedit.php of Moodle through 3.7.2 allows authenticated users (Teacher and above) to inject JavaScript into the session of another user (e.g., enrolled student or site administrator) via the introeditor[text] parameter. NOTE: the discoverer and vendor disagree on whether Moodle customers have a reasonable expectation that anyone authenticated as a Teacher can be trusted with the ability to add arbitrary JavaScript (this ability is not documented on Moodle's Teacher_role page). Because the vendor has this expectation, they have stated "this report has been closed as a false positive, and not a bug." (2020-02-11, CVE-2019-18210)

A vulnerability was found in moodle before versions 3.6.3, 3.5.5, 3.4.8 and 3.1.17. Users with the "login as other users" capability (such as administrators/managers) can access other users' Dashboards, but the JavaScript those other users may have added to their Dashboard was not being escaped when being viewed by the user logging in on their behalf. (2019-03-27, CVE-2019-3847)

A flaw was found in Moodle versions 3.6 to 3.6.1, 3.5 to 3.5.3, 3.4 to 3.4.6, 3.1 to 3.1.15 and earlier unsupported versions. The 'manage groups' capability did not have the 'XSS risk' flag assigned to it, but does have that access in certain places. Note that the capability is intended for use by trusted users, and is only assigned to teachers and managers by default. (2019-03-25, CVE-2019-3808)

A flaw was found in moodle versions 3.6 to 3.6.1, 3.5 to 3.5.3, 3.4 to 3.4.6, 3.1 to 3.1.15 and earlier unsupported versions. The /userpix/ page did not escape users' full names, which are included as text when hovering over profile images. Note this page is not linked to by default and its access is restricted. (2019-03-25, CVE-2019-3810)

moodle before versions 3.5.2, 3.4.5, 3.3.8 is vulnerable to a boost theme - blog search GET parameter insufficiently filtered. The breadcrumb navigation provided by Boost theme when displaying search results of a blog were insufficiently filtered, which could result in reflected XSS if a user followed a malicious link containing JavaScript in the search parameter. (2018-09-17, CVE-2018-14631)

An issue was discovered in Moodle 3.x. An authenticated user is allowed to add HTML blocks containing scripts to their Dashboard; this is normally not a security issue because a personal dashboard is visible to this user only. Through this security vulnerability, users can move such a block to other pages where they can be viewed by other users. (2018-05-25, CVE-2018-1136)

In Moodle 3.x, there is XSS via a calendar event name. (2018-01-22, CVE-2018-1045)

Cross site scripting is an attack where a web page executes code that is injected by an adversary. It usually appears, when users input is presented. This attack can be used to impersonate a user, take over control of the session, or even steal API keys.

The attack can be executed e.g. when you application injects the request parameter directly into the HTML code of the page returned to the user:

https://server.com/confirmation?message=Transaction+Complete

what results in:

<span>Confirmation: Transaction Complete</span>

In that case the message can be modified to become a valid Javascript code, e.g.:

https://server.com/confirmation?message=<script>dangerous javascript code here</script>

and it will be executed locally by the user's browser with full access to the user's personal application/browser data:

<span>Confirmation: <script>dangerous javascript code here</script></span>