Pretty Google Calendar < 2.0.1 - Missing Authorization to Unauthenticated Google API Key Exposure

Description

The Pretty Google Calendar plugin for WordPress is vulnerable to unauthorized access of data due to a missing capability check on the pgcal_ajax_handler() function in all versions up to, and including, 2.0.0. This makes it possible for unauthenticated attackers to retrieve the Google API key set in the plugin's settings.