The Countdown Timer block – Display the event's date into a timer. plugin for WordPress is vulnerable to Information Exposure in all versions up to, and including, 1.2.4 via the [ctb] shortcode due to insufficient restrictions on which posts can be included. This makes it possible for authenticated attackers, with Contributor-level access and above, to extract data from password protected, private, or draft posts that they should not have access to.

The Countdown Block WordPress plugin before 1.1.2 does not have authorisation in the eb_write_block_css AJAX action, which allows any authenticated user, such as Subscriber, to modify post contents displayed to users.