Multiple cross-site scripting (XSS) vulnerabilities in the administrative backend in MyBB (aka MyBulletinBoard) before 1.8.4 allow remote authenticated users to inject arbitrary web script or HTML via the (1) MIME-type field in an add action in the config-attachment_types module to admin/index.php; (2) title or (3) short description field in an add action in the (a) config-mycode or (b) user-groups module to admin/index.php; (4) title field in an add action in the (c) forum-management or (d) tool-tasks module to admin/index.php; (5) name field in an add_set action in the style-templates module to admin/index.php; (6) title field in an add_template_group action in the style-templates module to admin/index.php; (7) name field in an add action in the config-post_icons module to admin/index.php; (8) "title to assign" field in an add action in the user-titles module to admin/index.php; or (9) username field in the config-banning module to admin/index.php.