Event Monster <= 1.3.8 - Contributor+ PHP Object Injection via Custom Meta

Description The plugin is vulnerable to PHP Object Injection via deserialization via shortcode of untrusted input from a custom meta value. This makes it possible for authenticated attackers, with contributor access and above, to inject a PHP Object. No POP chain is present in the vulnerable plugin. If a POP chain is present via an additional plugin or theme installed on the target system, it could allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code.