WordPress · Modern Events Calendar Lite · CVE-2021-24147
Name of the Vulnerable Software and Affected Versions:
Modern Events Calendar Lite WordPress plugin versions prior to 5.16.5
Description:
The issue is related to unvalidated input and lack of output encoding in the plugin. Specifically, the `mic comment` field, also known as 'Notes on time', is not properly sanitised when adding or editing an event. This allows users with privileges as low as author to add events containing a Cross-Site Scripting payload, which is triggered when viewing the event in the frontend.
Recommendations:
For versions prior to 5.16.5, update to version 5.16.5 or later to resolve the issue. As a temporary workaround, consider restricting access to the event editing feature to higher-privileged users until the update is applied. Additionally, avoid using the `mic comment` field in events until the issue is resolved.