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.