The Shibboleth authentication plugin in auth/shibboleth/index.php in Moodle through 2.3.11, 2.4.x before 2.4.11, and 2.5.x before 2.5.7 does not check whether a session ID is empty, which allows remote authenticated users to hijack sessions via crafted plugin interaction.

Multiple cross-site scripting (XSS) vulnerabilities in the advanced-grading implementation 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 authenticated users to inject arbitrary web script or HTML via a crafted (1) qualification or (2) rating field in a rubric.

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.

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 does not enforce certain capability requirements in (1) notes/index.php and (2) user/edit.php, which allows remote attackers to obtain potentially sensitive username and course information via a modified URL.

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 authenticated users to execute arbitrary code via a calculated question in a quiz.

Cross-site scripting (XSS) vulnerability in user/profile.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 authenticated users to inject arbitrary web script or HTML via the Skype ID profile field.

mod/imscp/locallib.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 a package with a manifest file containing an XML external entity declaration in conjunction with an entity reference, related to an XML External Entity (XXE) issue affecting IMSCP resources and the IMSCC format.

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 Repositories component 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 conduct PHP object injection attacks and execute arbitrary code via serialized data associated with an add-on.

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.

The My Home implementation in the block_html_pluginfile function in blocks/html/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 does not properly restrict file access, which allows remote attackers to obtain sensitive information by visiting an HTML block.

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.

login/token.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 creates a MoodleMobile web-service token with an infinite lifetime, which makes it easier for remote attackers to hijack sessions via a brute-force attack.

Multiple cross-site request forgery (CSRF) vulnerabilities in mod/assign/locallib.php in the Assignment subsystem 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 allow remote attackers to hijack the authentication of teachers for quick-grading requests.

Cross-site scripting (XSS) vulnerability in the quiz_question_tostring function in mod/quiz/editlib.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 allows remote authenticated users to inject arbitrary web script or HTML via a quiz question.

The time-validation implementation in (1) mod/feedback/complete.php and (2) mod/feedback/complete_guest.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 allows remote authenticated users to bypass intended restrictions on starting a Feedback activity by choosing an unavailable time.

badges/mybadges.php in Moodle 2.5.x before 2.5.5 and 2.6.x before 2.6.2 does not properly track the user to whom a badge was issued, which allows remote authenticated users to modify the visibility of an arbitrary badge via unspecified vectors.

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.

Cross-site request forgery (CSRF) vulnerability in enrol/imsenterprise/importnow.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 allows remote attackers to hijack the authentication of administrators for requests that import an IMS Enterprise file.

The identity-reporting implementations in mod/forum/renderer.php and mod/quiz/override_form.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 do not properly restrict the display of e-mail addresses, which allows remote authenticated users to obtain sensitive information by using the (1) Forum or (2) Quiz module.