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.

The generate_password function 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 a sufficient number of possible temporary passwords, which allows remote attackers to obtain access via a brute-force attack.

mod/lti/launch.php in the LTI module 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 performs access control at the course level rather than at the activity level, which allows remote authenticated users to bypass the mod/lti:view capability requirement by viewing an activity instance.

The forum_print_latest_discussions function in mod/forum/lib.php in Moodle through 2.4.11, 2.5.x before 2.5.8, 2.6.x before 2.6.5, and 2.7.x before 2.7.2 allows remote authenticated users to bypass the individual answer-posting requirement without the mod/forum:viewqandawithoutposting capability, and discover an author's username, by leveraging the student role and visiting a Q&A forum.

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.

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 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.

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.

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.