The Calendar Event Multi View WordPress plugin before 1.4.07 does not have any authorisation and CSRF checks in place when creating an event, and is also lacking sanitisation as well as escaping in some of the event fields. This could allow unauthenticated attackers to create arbitrary events and put Cross-Site Scripting payloads in it.
CWE-79, CWE-862, CWE-352, CWE-862