Cross-site scripting (XSS) vulnerability in the Admin control panel in MyBB (aka MyBulletinBoard) before 1.8.8 and MyBB Merge System before 1.8.8 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.

MyBB (aka MyBulletinBoard) before 1.8.8 on Windows and MyBB Merge System before 1.8.8 on Windows allow remote attackers to overwrite arbitrary CSS files via vectors related to "style import."

Cross-site scripting (XSS) vulnerability in member validation in MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 might allow remote attackers to inject arbitrary web script or HTML via unspecified vectors.

Cross-site scripting (XSS) vulnerability in MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 might allow remote attackers to inject arbitrary web script or HTML via vectors related to login.

Cross-site scripting (XSS) vulnerability in the quick edit function in xmlhttp.php in MyBB (aka MyBulletinBoard) before 1.8.5 allows remote attackers to inject arbitrary web script or HTML via the content of a post.

Unspecified vulnerability in MyBB (aka MyBulletinBoard) before 1.8.4 has unknown attack vectors related to "Group join request notifications sent to wrong group leaders."

The cache handler in MyBB (aka MyBulletinBoard) before 1.8.4 does not properly check the encoding of input to the var_export function, which allows attackers to have an unspecified impact via unknown vectors.

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.

Cross-site scripting (XSS) vulnerability in the MyCode editor in MyBB (aka MyBulletinBoard) before 1.8.4 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.

Cross-site scripting (XSS) vulnerability in member.php in MyBB (aka MyBulletinBoard) before 1.8.4 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.