The WebToffee WooCommerce PDF Invoices, Packing Slips, Delivery Notes & Shipping Labels plugin for WordPress is vulnerable to Insecure Direct Object Reference in versions up to, and including, 5.0.2 via the 'email' parameter of the guest printdocumentfromthemaillink handler dispatched from printwindow() on init. This is due to the handler authorizing access to an order's printable documents when the attacker-supplied (base64-encoded) 'email' equals the order's billing email — a non-secret identifier — instead of requiring the WooCommerce orderkey. This makes it possible for unauthenticated attackers, when the site is configured to allow guest access to documents ('wtpklistprintbuttonaccessfor' != 'loggedin'), to retrieve any other customer's invoice, packing slip, delivery note, dispatch label or shipping label — including customer name, billing/shipping address, phone number, purchased products, prices, taxes and invoice metadata — by knowing the target order ID and the associated billing email address.

The WebToffee WooCommerce PDF Invoices, Packing Slips, Delivery Notes & Shipping Labels plugin for WordPress is vulnerable to Directory Traversal in all versions up to, and including, 4.9.8 via the getimagesrcinbase64 function. This makes it possible for authenticated attackers, with subscriber-level access and above, to read the contents of arbitrary files on the server, which can contain sensitive information. The base64-encoded file contents are embedded into the cached invoice HTML and served directly to the attacker via the plugin's own Print/Download invoice endpoints, which require only a valid nonce and access key.