Vulnerability in Payment Gateway For Paypal On Woocommerce

CVE-2026-16621

The Payment Gateway for PayPal on WooCommerce WordPress plugin before 9.2.1 does not verify that payment actually succeeded before completing an order in its PayPal return handler: it reads attacker-controlled parameters, performs no amount comparison and no order-ownership check, and completes the order even when the server-side gateway verification fails, allowing an unauthenticated attacker to mark arbitrary orders as paid without paying.

Published · last modified .

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

EPSS: 0.002 (4.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 5th percentile — 4.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-16621: held from 0.001 to 0.002.

EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.000

Affected products

  • Payment Gateway For Paypal On Woocommerce — versions 0

References

Frequently asked questions

What is CVE-2026-16621?
CVE-2026-16621 is a medium-severity vulnerability in Payment Gateway For Paypal On Woocommerce, classified under CWE-345 INSUFFICIENT VERIFICATION OF DATA AUTHENTICITY. CVSS score: 5.3/10. Published 2026-08-12.
How severe is CVE-2026-16621?
Medium severity. CVSS v3 base score is 5.3 out of 10.