The Advanced Cron Manager WordPress plugin before 2.5.7 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup)
The Advanced Cron Manager WordPress plugin before 2.4.2 and Advanced Cron Manager Pro WordPress plugin before 2.5.3 do not have authorisation checks in some of their AJAX actions, allowing any authenticated users, such as subscriber to call them and add or remove events as well as schedules for example