CVE-2026-18027

WebToffee WooCommerce PDF Invoices, Packing Slips, Delivery Notes & Shipping Labels <= 4.9.8 - Authenticated (Subscriber+) Arbitrary File Read via 'customer_note' Parameter

2026-08-22 10:37
daroo

Strategic Overview

Status
Patched in 5.0.0
Affected Plugin
WebToffee WooCommerce PDF Invoices, Packing Slips, Delivery Notes & Shipping Labels
Affected Version
<= 4.9.8
CVSS
6.5Medium
Weakness type
CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CVE
CVE-2026-18027
View all WebToffee WooCommerce PDF Invoices, Packing Slips, Delivery Notes & Shipping Labels vulnerabilities

At a glance

CVE-2026-18027 is a medium-severity Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in the WebToffee WooCommerce PDF Invoices, Packing Slips, Delivery Notes & Shipping Labels WordPress plugin, affecting versions <= 4.9.8. It carries a CVSS score of 6.5 (reachable over the network; low attack complexity; high confidentiality impact). Exploitation requires an authenticated account at Subscriber level or above. The issue is fixed in version 5.0.0; sites on affected versions should update now. Disclosed August 2026, reported by daroo.

Vulnerability Overview

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 get_image_src_in_base64 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.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no interaction from a victim user. A successful exploit has high impact on confidentiality.

CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Reaching this weakness in WebToffee WooCommerce PDF Invoices, Packing Slips, Delivery Notes & Shipping Labels <= 4.9.8 takes an account at Subscriber level or above. Path traversal happens when user-controlled text is used to build a filesystem path without being constrained to an intended directory, so sequences like ../ walk the resolved path somewhere else.

Depending on the operation, it means reading files outside the intended folder — wp-config.php being the usual target — or writing to and deleting paths the web server can touch. For WebToffee WooCommerce PDF Invoices, Packing Slips, Delivery Notes & Shipping Labels the fix is 5.0.0: builds <= 4.9.8 are affected, anything from 5.0.0 onward is not.

Remediation

Update to version 5.0.0, or a newer patched version

How does WordSec protect against this?

An attacker needs Subscriber access first, so the firewall sees the attempt as traffic from a logged-in account: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: WebToffee WooCommerce PDF Invoices, Packing Slips, Delivery Notes & Shipping Labels 5.0.0 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-18027https://www.wordfence.com/threat-intel/vulnerabilities/id/a46f270f-d9cb-4bc1-8e10-3fc6646e1d78https://nvd.nist.gov/vuln/detail/CVE-2026-18027

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C