mod/forum/classes/post_form.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 does not enforce the moodle/site:accessallgroups capability requirement before proceeding with a post to all groups, which allows remote authenticated users to bypass intended access restrictions by leveraging two or more group memberships.

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.

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.

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.

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 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.