WP Simple Galleries <= 1.34 - Authenticated (Contributor+) PHP Object Injection

The WP Simple Galleries plugin for WordPress is vulnerable to PHP Object Injection in versions up to, and including, 1.34 via deserialization of untrusted input from the 'wpsimplegallery_gallery' post meta via 'wpsgallery' shortcode. This allows authenticated attackers, with contributor-level permissions 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.