Cross-site scripting (XSS) vulnerability in Mahara before 1.5.12, 1.6.x before 1.6.7, and 1.7.x before 1.7.3 allows remote attackers to inject arbitrary web script or HTML via the Host header to lib/web.php.
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.