The CMB2 plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 2.10.1 via deserialization of untrusted input from the text_datetime_timestamp_timezone field. This makes it possible for authenticated attackers, with contributor access or higher, 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. Please note that the plugin is a developer toolkit. For the vulnerability to become exploitable, the presence of a metabox activation in your code (via functions.php for example) is required.