# Invoicing with InvoiceXpress for WooCommerce <= 9.1 - Unauthenticated Sensitive Information Exposure via Predictable Document PDF File Names

- **ID:** WPSEC-2026-1030
- **Plugin:** Invoicing with InvoiceXpress for WooCommerce – Free (`woo-billing-with-invoicexpress`), https://wordpress.org/plugins/woo-billing-with-invoicexpress/
- **Affected versions:** all versions before 10.0
- **Fixed in:** 10.0 (Update to 10.0 or later.)
- **Severity:** Medium 5.9 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N)
- **Weakness:** CWE-552
- **Usage among sites WPSec scans:** plugin Low, affected versions None seen (as of 2026-10-15)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/woo-billing-with-invoicexpress
- **Fix released:** 2026-10-14
- **Published:** 2026-10-15
- **URL:** https://wpsec.com/vuln/WPSEC-2026-1030/

## Description

The Invoicing with InvoiceXpress for WooCommerce plugin for WordPress is vulnerable to Sensitive Information Exposure in all versions up to, and including, 9.1. Generated invoicing document PDFs (invoices, receipts, quotes, proformas and similar) were stored in a publicly accessible folder under wp-content/uploads/invoicexpress/documents/, without any access restriction. Their file names were built from the document type and sequence number plus only a short, insufficiently random suffix. This makes it possible for unauthenticated attackers to guess file URLs and download other customers' invoicing documents containing their personal and billing details.

## References

- https://wpsec.com/vuln/WPSEC-2026-1030/
- https://plugins.svn.wordpress.org/woo-billing-with-invoicexpress/tags/10.0/
- https://wordpress.org/plugins/woo-billing-with-invoicexpress/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-1030/

License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Free to use, share and adapt, also commercially, if you credit WPSec and link to this advisory.