In Moodle 2.x and 3.x, text injection can occur in email headers, potentially leading to outbound spam.

Multiple open redirect vulnerabilities in Moodle through 2.5.9, 2.6.x before 2.6.11, 2.7.x before 2.7.8, and 2.8.x before 2.8.6 allow remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via vectors involving an error page that links to a URL from an HTTP Referer header.

repository/s3/S3.php in the Amazon S3 library 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 does not verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate, related to an incorrect CURLOPT_SSL_VERIFYHOST value.

Multiple open redirect vulnerabilities in Moodle 2.2.x before 2.2.7, 2.3.x before 2.3.4, and 2.4.x before 2.4.1 allow remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via vectors related to (1) backup/backupfilesedit.php, (2) comment/comment_post.php, (3) course/switchrole.php, (4) mod/wiki/filesedit.php, (5) tag/coursetags_add.php, or (6) user/files.php.

repository/alfresco/lib.php in Moodle through 2.3.11, 2.4.x before 2.4.9, 2.5.x before 2.5.5, and 2.6.x before 2.6.2 places a session key in a URL, which allows remote attackers to bypass intended Alfresco Repository file restrictions by impersonating a file's owner.

A vulnerability was found in moodle before versions 3.6.3, 3.5.5, 3.4.8 and 3.1.17. Links within assignment submission comments would open directly (in the same window). Although links themselves may be valid, opening within the same window and without the no-referrer header policy made them more susceptible to exploits.

A vulnerability was found in Moodle 3.7 to 3.7.1, 3.6 to 3.6.5, 3.5 to 3.5.7 and earlier unsupported versions, where the mobile launch endpoint contained an open redirect in some circumstances, which could result in a user's mobile access token being exposed. (Note: This does not affect sites with a forced URL scheme configured, mobile service disabled, or where the mobile app login method is "via the app").

A vulnerability was found in Moodle 3.7 to 3.7.1, 3.6 to 3.6.5, 3.5 to 3.5.7 and earlier unsupported versions, where forum subscribe link contained an open redirect if forced subscription mode was enabled. If a forum's subscription mode was set to "forced subscription", the forum's subscribe link contained an open redirect.

A vulnerability was found in Moodle 3.7 to 3.7.3, 3.6 to 3.6.7, 3.5 to 3.5.9 and earlier where an open redirect existed in the Lesson edit page.

A flaw was found in Moodle before 3.7, 3.6.4, 3.5.6, 3.4.9 and 3.1.18. The form to upload cohorts contained a redirect field, which was not restricted to internal URLs.

Open redirect vulnerability in the clean_param function in lib/moodlelib.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 redirect users to arbitrary web sites and conduct phishing attacks via vectors involving an HTTP Referer header that has a substring match with a local URL.

Moodle 2.0.1 allows remote attackers to obtain sensitive information via a direct request to a .php file, which reveals the installation path in an error message, as demonstrated by webservice/xmlrpc/locallib.php and certain other files.

Moodle 2.0.x before 2.0.2 does not use the forceloginforprofiles setting for course-profiles access control, which makes it easier for remote attackers to obtain potentially sensitive information via vectors involving use of a search engine, as demonstrated by the search functionality of Google, Yahoo!, Wrensoft Zoom, MSN, Yandex, and AltaVista.

The course participation report required additional checks to prevent roles being displayed which the user did not have access to view.

calendar/externallib.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 provides calendar-event data without considering whether an activity is hidden, which allows remote authenticated users to obtain sensitive information via a web-service request.

admin/tool/monitor/lib.php in Event Monitor in Moodle 2.8.x before 2.8.11, 2.9.x before 2.9.5, and 3.0.x before 3.0.3 does not consider the moodle/course:viewhiddencourses capability, which allows remote authenticated users to discover hidden course names by subscribing to a rule.

lib/ajax/getnavbranch.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, when the forcelogin feature is enabled, allows remote attackers to obtain sensitive category-detail information from the navigation branch by leveraging the guest role for an Ajax request.

user/index.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 grants excessive authorization on the basis of the moodle/course:viewhiddenuserfields capability, which allows remote authenticated users to discover student e-mail addresses by leveraging the teacher role and reading a Participants list.

Moodle 1.8 before 1.8.11 and 1.9 before 1.9.7 stores (1) password hashes and (2) unspecified "secrets" in backup files, which might allow attackers to obtain sensitive information.

The LAMS module (mod/lams) for Moodle 1.8 before 1.8.11 and 1.9 before 1.9.7 stores the (1) username, (2) firstname, and (3) lastname fields within the user table, which allows attackers to obtain user account information via unknown vectors.

The (1) core_enrol_get_course_enrolment_methods and (2) enrol_self_get_instance_info web services in Moodle through 2.6.11, 2.7.x before 2.7.12, 2.8.x before 2.8.10, 2.9.x before 2.9.4, and 3.0.x before 3.0.2 do not consider the moodle/course:viewhiddencourses capability, which allows remote authenticated users to obtain sensitive information via a web-service request.

Multiple unspecified authentication plugins in Moodle 1.8 before 1.8.11 and 1.9 before 1.9.7 store the MD5 hashes for passwords in the user table, even when the cached hashes are not used by the plugin, which might make it easier for attackers to obtain credentials via unspecified vectors.

Cross-site request forgery (CSRF) vulnerability in admin/registration/register.php in 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 allows remote attackers to hijack the authentication of administrators for requests that send statistics to an arbitrary hub URL.

The rating component in Moodle through 2.6.11, 2.7.x before 2.7.10, 2.8.x before 2.8.8, and 2.9.x before 2.9.2 mishandles group-based authorization checks, which allows remote authenticated users to obtain sensitive information by reading a rating value.

H5P metadata automatically populated the author with the user's username, which could be sensitive information.

Separate Groups mode restrictions were not honoured in the forum summary report, which would display users from other groups.

The account-confirmation feature in login/confirm.php in Moodle through 2.5.9, 2.6.x before 2.6.11, 2.7.x before 2.7.8, and 2.8.x before 2.8.6 allows remote attackers to obtain sensitive full-name information by attempting to self-register.

The last time a user accessed the mobile app is displayed on their profile page, but should be restricted to users with the relevant capability (site administrators by default). Moodle versions 3.10 to 3.10.3 are affected.

It was possible for a student to view their quiz grade before it had been released, using a quiz web service. 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

message/index.php in Moodle through 2.5.9, 2.6.x before 2.6.9, 2.7.x before 2.7.6, and 2.8.x before 2.8.4 does not consider the moodle/site:readallmessages capability before accessing arbitrary conversations, which allows remote authenticated users to obtain sensitive personal-contact and unread-message-count information via a modified URL.

mod/lti/ajax.php in Moodle through 2.5.9, 2.6.x before 2.6.7, 2.7.x before 2.7.4, and 2.8.x before 2.8.2 does not consider the moodle/course:manageactivities and mod/lti:addinstance capabilities before proceeding with registered-tool list searches, which allows remote authenticated users to obtain sensitive information via requests to the LTI Ajax service.

calendar/externallib.php in Moodle through 2.5.9, 2.6.x before 2.6.7, 2.7.x before 2.7.4, and 2.8.x before 2.8.2 allows remote authenticated users to obtain sensitive calendar-event information via a web-services request.

An issue was discovered in Moodle 3.x. Students who posted on forums and exported the posts to portfolios can download any stored Moodle file by changing the download URL.

lib/classes/grades_external.php in Moodle 2.7.x before 2.7.3 does not consider the moodle/grade:viewhidden capability before displaying hidden grades, which allows remote authenticated users to obtain sensitive information by leveraging the student role to access the get_grades web service.

mod/data/edit.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 sets a certain group ID to zero upon a database-entry change, which allows remote authenticated users to obtain sensitive information by accessing the database after an edit by a teacher.

lib/phpunit/bootstrap.php in Moodle 2.6.x before 2.6.6 and 2.7.x before 2.7.3 allows remote attackers to obtain sensitive information via a direct request, which reveals the full path in an error message.

A flaw was found in moodle before versions 3.5.1, 3.4.4, 3.3.7, 3.1.13. It was possible for the core_course_get_categories web service to return hidden categories, which should be omitted when fetching course categories.

In Moodle 3.x, quiz web services allow students to see quiz results when it is prohibited in the settings.

mod/lti/service.php 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 allows remote attackers to read arbitrary files via an XML external entity declaration in conjunction with an entity reference, related to an XML External Entity (XXE) issue.

The blind-marking implementation 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 authenticated users to de-anonymize student identities by (1) using a screen reader or (2) reading the HTML source.

enrol/index.php in Moodle 2.6.x before 2.6.3 does not check for the moodle/course:viewhiddencourses capability before listing hidden courses, which allows remote attackers to obtain sensitive name and summary information about these courses by leveraging the guest role and visiting a crafted URL.

lib/filelib.php in Moodle through 2.2.11, 2.3.x before 2.3.10, 2.4.x before 2.4.7, and 2.5.x before 2.5.3 does not send "Cache-Control: private" HTTP headers, which allows remote attackers to obtain sensitive information by requesting a file that had been previously retrieved by a caching proxy server.

It was possible for some users without permission to view other users' full names to do so via the online users block in moodle before 3.10.2, 3.9.5, 3.8.8, 3.5.17.

In Moodle 3.3, the course overview block reveals activities in hidden courses.

The chat functionality in Moodle 2.0.x before 2.0.5 and 2.1.x before 2.1.2 allows remote authenticated users to discover the name of any user via a beep operation.

repository/webdav/lib.php in Moodle 2.x through 2.1.10, 2.2.x before 2.2.8, 2.3.x before 2.3.5, and 2.4.x before 2.4.2 includes the WebDAV password in the configuration form, which allows remote authenticated administrators to obtain sensitive information by configuring an instance.

calendar/managesubscriptions.php in Moodle 2.4.x before 2.4.2 does not consider capability requirements before displaying calendar subscriptions, which allows remote authenticated users to obtain potentially sensitive information by leveraging the student role.

mod/lesson/pagetypes/matching.php in Moodle through 2.2.11, 2.3.x before 2.3.8, 2.4.x before 2.4.5, and 2.5.x before 2.5.1 allows remote authenticated users to obtain sensitive answer information by reading the HTML source code of a document.

lib/setuplib.php in Moodle through 2.1.10, 2.2.x before 2.2.8, 2.3.x before 2.3.5, and 2.4.x before 2.4.2 allows remote attackers to obtain sensitive information via an invalid request, which reveals the absolute path in an exception message.

Moodle 2.x through 2.1.10, 2.2.x before 2.2.8, 2.3.x before 2.3.5, and 2.4.x before 2.4.2 allows remote authenticated administrators to obtain sensitive information from the external repositories of arbitrary users by leveraging the login_as feature.