The Mang Board WP plugin for WordPress is vulnerable to Missing Authorization via Authentication Cookie Forgery in all versions up to, and including, 2.3.7. This is due to flawed HMAC generation in the mbw_get_hash_key() function that uses the current user's identity instead of the cookie username parameter when a WordPress user is logged in, combined with insufficient validation in mbw_validate_auth_cookie(). This makes it possible for authenticated attackers, with subscriber-level access and above, to forge administrator authentication cookies and change administrator passwords to achieve complete site takeover.