Description
WordPress Plugin The Events Calendar Countdown Addon is prone to a security bypass vulnerability. Exploiting this issue may allow attackers to perform otherwise restricted actions and subsequently download and extract a remote ZIP file on the blog, which can lead to remote code execution. WordPress Plugin The Events Calendar Countdown Addon version 1.3.1 is vulnerable; prior versions may also be affected.
Remediation
Update to plugin version 1.4 or latest
References
https://blog.nintechnet.com/8-wordpress-plugins-fixed-high-severity-vulnerability/
https://plugins.svn.wordpress.org/countdown-for-the-events-calendar/trunk/readme.txt