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.

Cross-site scripting (XSS) vulnerability in Moodle before 1.6.8, 1.7 before 1.7.6, 1.8 before 1.8.7, and 1.9 before 1.9.3 allows remote attackers to inject arbitrary web script or HTML via a Wiki page name (aka page title).

The _bad_protocol_once function in phpgwapi/inc/class.kses.inc.php in KSES, as used in eGroupWare before 1.4.003, Moodle before 1.8.5, and other products, allows remote attackers to bypass HTML filtering and conduct cross-site scripting (XSS) attacks via a string containing crafted URL protocols.

Multiple cross-site scripting (XSS) vulnerabilities in auth/db/auth.php in Moodle through 2.6.11, 2.7.x before 2.7.13, 2.8.x before 2.8.11, 2.9.x before 2.9.5, and 3.0.x before 3.0.3 allow remote attackers to inject arbitrary web script or HTML via an external DB profile field.

Cross-site scripting (XSS) vulnerability in the advanced-search feature in mod_data in Moodle through 2.6.11, 2.7.x before 2.7.13, 2.8.x before 2.8.11, 2.9.x before 2.9.5, and 3.0.x before 3.0.3 allows remote attackers to inject arbitrary web script or HTML via a crafted field in a URL, as demonstrated by a search form field.

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.

Cross-site scripting (XSS) vulnerability in the search_pagination function in course/classes/management_renderer.php in Moodle 2.8.x before 2.8.10, 2.9.x before 2.9.4, and 3.0.x before 3.0.2 allows remote attackers to inject arbitrary web script or HTML via a crafted search string.

Cross-site scripting (XSS) vulnerability in install.php for Moodle 1.8.3, and possibly other versions before 1.8.4, allows remote attackers to inject arbitrary web script or HTML via the dbname parameter. NOTE: this issue only exists until the installation is complete.

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.

Moodle 3.x has XSS in the contact form on the "non-respondents" page in non-anonymous feedback.

Moodle through 2.6.11, 2.7.x before 2.7.11, 2.8.x before 2.8.9, and 2.9.x before 2.9.3 does not properly restrict the availability of Flowplayer, which allows remote attackers to conduct cross-site scripting (XSS) attacks via a crafted .swf file.

Cross-site scripting (XSS) vulnerability in the user_get_user_details function in user/lib.php in Moodle through 2.6.11, 2.7.x before 2.7.9, 2.8.x before 2.8.7, and 2.9.x before 2.9.1 allows remote attackers to inject arbitrary web script or HTML by leveraging absence of an external_format_text call in a web service.

Multiple cross-site scripting (XSS) vulnerabilities in the SCORM module in Moodle through 2.6.11, 2.7.x before 2.7.9, 2.8.x before 2.8.7, and 2.9.x before 2.9.1 allow remote attackers to inject arbitrary web script or HTML via a crafted organization name to (1) mod/scorm/player.php or (2) mod/scorm/prereqs.php.

Cross-site scripting (XSS) vulnerabilities in Moodle CMS on or before 3.1.2 allow remote attackers to inject arbitrary web script or HTML via the s_additionalhtmlhead, s_additionalhtmltopofbody, and s_additionalhtmlfooter parameters.

A flaw was found in moodle. This vulnerability, known as Cross-Site Scripting (XSS), occurs due to insufficient checks on user-provided data in the formula editor's arithmetic expression fields. A remote attacker could inject malicious code into these fields. When other users view these expressions, the malicious code would execute in their web browsers, potentially compromising their data or leading to unauthorized actions.

A flaw was found in Moodle. This cross-site scripting (XSS) vulnerability, caused by improper sanitization of AI prompt responses, allows attackers to inject malicious HTML or script into web pages. When other users view these compromised pages, their sessions could be stolen, or the user interface could be manipulated.

A flaw was found in mooodle. A remote attacker could exploit a reflected Cross-Site Scripting (XSS) vulnerability in the policy tool return URL. This vulnerability arises from insufficient sanitization of URL parameters, allowing attackers to inject malicious scripts through specially crafted links. Successful exploitation could lead to information disclosure or arbitrary client-side script execution within the user's browser.

Cross-site scripting (XSS) vulnerability in the phpCAS client library before 1.1.0, as used in Moodle 1.8.x before 1.8.12 and 1.9.x before 1.9.8, allows remote attackers to inject arbitrary web script or HTML via a crafted URL, which is not properly handled in an error message.

Cross-site scripting (XSS) vulnerability in course/editsection.html in Moodle 1.9.x before 1.9.14 allows remote authenticated users to inject arbitrary web script or HTML via crafted data.

Multiple cross-site scripting (XSS) vulnerabilities in the media-filter implementation in filter/mediaplugin/filter.php in Moodle 1.9.x before 1.9.11 and 2.0.x before 2.0.2 allow remote attackers to inject arbitrary web script or HTML via vectors involving (1) Flash Video (aka FLV) files and (2) YouTube videos.

lib/setup.php in Moodle through 2.4.11, 2.5.x before 2.5.9, 2.6.x before 2.6.6, and 2.7.x before 2.7.3 does not provide charset information in HTTP headers, which might allow remote attackers to conduct cross-site scripting (XSS) attacks via UTF-7 characters during interaction with AJAX scripts.

Cross-site scripting (XSS) vulnerability in the get_description function in lib/classes/event/user_login_failed.php in Moodle 2.7.x before 2.7.1 allows remote attackers to inject arbitrary web script or HTML via a crafted username that is improperly handled during the logging of an invalid login attempt.

Multiple cross-site scripting (XSS) vulnerabilities in badges/renderer.php in Moodle 2.5.x before 2.5.7, 2.6.x before 2.6.4, and 2.7.x before 2.7.1 allow remote attackers to inject arbitrary web script or HTML via an external badge.

Multiple cross-site scripting (XSS) vulnerabilities in Moodle through 2.3.11, 2.4.x before 2.4.11, 2.5.x before 2.5.7, 2.6.x before 2.6.4, and 2.7.x before 2.7.1 allow remote attackers to inject arbitrary web script or HTML via vectors that trigger an AJAX exception dialog.

Multiple cross-site scripting (XSS) vulnerabilities in admin/tool/task/scheduledtasks.php in Moodle 2.7.x before 2.7.1 allow remote attackers to inject arbitrary web script or HTML via vectors that trigger a crafted (1) error or (2) success message for a scheduled task.

A Cross-Site Scripting (XSS) vulnerability exists in the way MOODLE 3.10.9 handles user input within the "GET /?lang=" URL parameter.

Cross-site scripting (XSS) vulnerability in the URL downloader repository in repository/url/lib.php in Moodle through 2.3.11, 2.4.x before 2.4.10, 2.5.x before 2.5.6, and 2.6.x before 2.6.3 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.

Cross-site scripting (XSS) vulnerability in io.swf in the IO Utility component in Yahoo! YUI 3.0.0 through 3.9.1, as used in Moodle through 2.1.10, 2.2.x before 2.2.11, 2.3.x before 2.3.8, 2.4.x before 2.4.5, 2.5.x before 2.5.1, and other products, allows remote attackers to inject arbitrary web script or HTML via a crafted string in a URL.

Cross-site scripting (XSS) vulnerability in uploader.swf in the Uploader component in Yahoo! YUI 3.2.0 through 3.9.1, as used in Moodle through 2.1.10, 2.2.x before 2.2.11, 2.3.x before 2.3.8, 2.4.x before 2.4.5, 2.5.x before 2.5.1, and other products, allows remote attackers to inject arbitrary web script or HTML via a crafted string in a URL.

The course upload preview contained an XSS risk for users uploading unsafe data.

The CSV grade import method contained an XSS risk for users importing the spreadsheet, if it contained unsafe content.

Multiple cross-site scripting (XSS) vulnerabilities in Moodle through 2.2.11, 2.3.x before 2.3.9, 2.4.x before 2.4.6, and 2.5.x before 2.5.2 allow remote attackers to inject arbitrary web script or HTML via a crafted blog link within an RSS feed.

Multiple cross-site scripting (XSS) vulnerabilities in lib/conditionlib.php in Moodle 2.4.x before 2.4.5 and 2.5.x before 2.5.1 allow remote attackers to inject arbitrary web script or HTML via the conditional access rule value of a user field.

Insufficient escaping of calendar event titles resulted in a stored XSS risk in the event deletion prompt.

Cross-site scripting (XSS) vulnerability in view.php in Moodle 1.4.2 and earlier allows remote attackers to inject arbitrary web script or HTML via the search parameter.

Multiple cross-site scripting (XSS) vulnerabilities in mod/lti/typessettings.php in Moodle 2.2.x before 2.2.4 and 2.3.x before 2.3.1 allow remote attackers to inject arbitrary web script or HTML via the (1) lti_typename or (2) lti_toolurl parameter.

Virtual Programming Lab for Moodle up to v4.2.3 was discovered to contain a cross-site scripting (XSS) vulnerability via the component vplide.js.

Additional sanitizing was required when opening the equation editor to prevent a stored XSS risk when editing another user's equation.

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.

Cross-site scripting (XSS) vulnerability in mod/wiki/lang/en/wiki.php in Moodle 2.0.x before 2.0.5 and 2.1.x before 2.1.2 allows remote attackers to inject arbitrary web script or HTML via the section parameter.

Cross-site scripting (XSS) vulnerability in the tag autocomplete functionality in Moodle 1.9.x before 1.9.11 and 2.0.x before 2.0.2 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.

Cross-site scripting (XSS) vulnerability in the print_object function in lib/datalib.php in Moodle 2.0.x before 2.0.6 and 2.1.x before 2.1.3, when a developer debugging script is enabled, allows remote attackers to inject arbitrary web script or HTML via vectors involving object states.

Cross-site scripting (XSS) vulnerability in mod/wiki/pagelib.php in Moodle 2.0.x before 2.0.5 and 2.1.x before 2.1.2 allows remote authenticated users to inject arbitrary web script or HTML via a wiki comment.

Multiple cross-site scripting (XSS) vulnerabilities in the course-tags functionality in tag/coursetags_more.php in Moodle 2.0.x before 2.0.2 allow remote attackers to inject arbitrary web script or HTML via the (1) sort or (2) show parameter.

Cross-site scripting (XSS) vulnerability in the Spike PHPCoverage (aka spikephpcoverage) library, as used in Moodle 2.0.x before 2.0.2 and other products, allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.

Multiple cross-site scripting (XSS) vulnerabilities in lib/weblib.php in Moodle 1.9.x before 1.9.12 allow remote attackers to inject arbitrary web script or HTML via vectors related to URL encoding.

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.

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.

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.

If the algebra filter was enabled but not functional (eg the necessary binaries were missing from the server), it presented an XSS risk.