Partial Shipment for Woocommerce <= 3.4 - Missing Authorization to Authenticated (Subscriber+) Arbitrary Settings Modification via wxp_order_shipment, wxp_order_item_shipment, and wxp_order_set_shipped AJAX Actions

The Partial Shipment for Woocommerce plugin for WordPress is vulnerable to Missing Authorization in versions up to, and including, 3.4 via the wxp_order_shipment, wxp_order_item_shipment, and wxp_order_set_shipped AJAX actions. This is due to the AJAX handlers in woocommerce-partial-shipment.php (registered at lines 60–62 and implemented at lines 228, 263, and 291) lacking both capability checks and nonce verification, and not validating the calling user's ownership of the supplied order_id. This makes it possible for authenticated attackers, with Subscriber-level access and above, to read arbitrary order item details (names, quantities, shipped counts) belonging to any customer and to modify the shipment status / shipped quantities of any order, which can also trigger order status transitions via the wxp_order_status action.