The Vchasno Kasa plugin for WordPress is vulnerable to unauthorized access of data due to a missing capability check on the mrkv_vchasno_kasa_wc_do_metabox_action() function in all versions up to, and including, 1.0.3. This makes it possible for unauthenticated attackers to generate invoices for arbitrary orders.
https://plugins.trac.wordpress.org/browser/mrkv-vchasno-kasa/trunk/classes/mrkv-setup.php#L395