Description
The PDF Invoices & Packing Slips for WooCommerce plugin for WordPress is vulnerable to Sensitive Information Exposure in all versions up to, and including, 5.16.5 via the 'invoice_number (via document filename)' parameter. This makes it possible for unauthenticated attackers to extract another customer's complete invoice PDF — including billing identity, shipping address, private order notes, line items, prices, dates, order ID, and invoice number — delivered directly to the attacker's email as an order confirmation attachment. Exploitation requires the plugin's yearly invoice number reset option to be enabled, and the attacker's guest-checkout order must trigger a processing email within 60 seconds of a victim order that shares the same yearly-reset invoice number.
References
https://www.wordfence.com/threat-intel/vulnerabilities/id/e68495ad-53ab-4c6b-aecc-1e4bfe34aa0d?source=cve
https://plugins.trac.wordpress.org/changeset?reponame=&old=3759839%40woocommerce-pdf-invoices-packing-slips&new=3759839%40woocommerce-pdf-invoices-packing-slips
https://plugins.trac.wordpress.org/browser/woocommerce-pdf-invoices-packing-slips/tags/5.16.4/includes/Main.php#L253
https://plugins.trac.wordpress.org/browser/woocommerce-pdf-invoices-packing-slips/tags/5.16.4/includes/Main.php#L239
https://plugins.trac.wordpress.org/browser/woocommerce-pdf-invoices-packing-slips/tags/5.16.4/includes/Main.php#L181
https://plugins.trac.wordpress.org/browser/woocommerce-pdf-invoices-packing-slips/tags/5.16.4/includes/Documents/Invoice.php#L146
https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-114613