Mail Mint < 1.31.1 - Unauthenticated PHP Object Injection in Arbitrary Form Fields

Description

The Mail Mint – Email Marketing, Newsletter, Email Automation & WooCommerce Emails plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 1.31.0 via deserialization of untrusted input in the 'handle_form_submission' function. This makes it possible for unauthenticated attackers to inject a PHP Object. The additional presence of a POP chain allows attackers to execute code on the server. The vulnerability was partially patched in version 1.23.1.