The Advanced Ads plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 1.52.1 via deserialization of untrusted input in the 'placement_slug' parameter. This makes it possible for authenticated attackers 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.