What is CVE-2026-103311?

CVE-2026-103311 is a medium-severity vulnerability in Coinbase Commerce Payment Gateway For Woocommerce, classified under Insufficient Verification of Data Authenticity. CVSS score: 5.3/10. Published 2026-10-19.

How severe is CVE-2026-103311?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Coinbase Commerce Payment Gateway For Woocommerce

CVE-2026-103311

The Coinbase Commerce Payment Gateway for WooCommerce WordPress plugin through 1.4.1 does not verify the authenticity of incoming payment webhook notifications, because the shared secret used to validate the request signature is empty by default and nothing rejects an unconfigured secret, allowing unauthenticated attackers to forge notifications that mark arbitrary orders as paid or cancel already-paid orders.

Published 2026-10-19 · last modified 2026-10-19.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Coinbase Commerce Payment Gateway For Woocommerce

Weakness classification (CWE)

CWE-345 — Insufficient Verification of Data Authenticity

References

wpscan.com/vulnerability/3d43ae6a-ca0d-49f9-aa3a-a584e5155efe/ (technical-description, exploit, vdb-entry)

Frequently asked questions

What is CVE-2026-103311?: CVE-2026-103311 is a medium-severity vulnerability in Coinbase Commerce Payment Gateway For Woocommerce, classified under Insufficient Verification of Data Authenticity. CVSS score: 5.3/10. Published 2026-10-19.
How severe is CVE-2026-103311?: Medium severity. CVSS v3 base score is 5.3 out of 10.