Invoice Generator <= 1.0.0 - Unauthenticated Account Takeover via Weak Password Reset Validation via 'reset_user_id' Parameter

The Invoice Generator plugin for WordPress is vulnerable to Account Takeover via Password Reset in all versions up to, and including, 1.0.0. This is due to the `pravel_invoice_change_password()` function being registered as a nopriv AJAX handler with no nonce verification and no authorization check, and performing a loose equality comparison between the supplied `reset_activation_code` POST parameter and the target user's stored `forgot_email` user meta — a check that trivially evaluates to true (`'' == ''`) for any user who has never initiated a forgot-password request, which applies to administrators under normal conditions. This makes it possible for unauthenticated attackers to supply an arbitrary user ID via the `reset_user_id` POST parameter, bypass the activation code check entirely by omitting `reset_activation_code`, and set the target account's password to an attacker-chosen value, enabling full takeover of any account on the site, including administrator accounts.