CVE-2026-9189
Medium · 5.3CVSS
5.3
EPSS
0.2%
Published
May 29, 2026
CISA due date
—
The record
The Contact Form 7 – PayPal & Stripe Add-on plugin for WordPress is vulnerable to Payment Bypass via Insufficient Verification of Data Authenticity in all versions up to, and including, 2.4.9. Although `cf7pp_paypal_ipn_handler()` correctly validates IPN authenticity by posting back to PayPal with `cmd=_notify-validate`, it fails to compare the IPN payload's `mc_gross` (payment amount), `mc_currency`, or `receiver_email` fields against the corresponding stored order values before passing the attacker-controlled `invoice` field directly to `cf7pp_complete_payment()`, which marks the order completed after only an integer cast with no amount verification. This makes it possible for unauthenticated attackers to mark arbitrary high-value pending orders as fully paid by making a minimal real PayPal payment and crafting an IPN whose `invoice` parameter references the targeted order, effectively completing purchases without tendering the required payment amount.
Affected packages
| Ecosystem | Package | Introduced | Fixed |
|---|
Related vulnerabilities
- CVE-2026-102682 Pipecat is an open-source Python framework for building real-time voice and multimodal… CWE-345
- CVE-2026-104850 MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and… CWE-345
- CVE-2026-102275 PyJWT is a Python implementation of JSON Web Token standards. CWE-345
- CVE-2026-102267 PyJWT is a Python implementation of JSON Web Token standards. CWE-345
- CVE-2026-19941 An inapplicable NSEC record may be accepted by a `named` resolver as proof that no… CWE-345
- CVE-2026-77955 In NLnet Labs Unbound 1.13.2 up to and including 1.26.1, a vulnerability in ZONEMD… CWE-345
- CVE-2026-89251 AVideo through commit c3edcc274c389816d434acadac07ee78eaf330c1 fails to validate ad… CWE-345
- CVE-2026-86809 The Persian Elementor WordPress plugin from 2.7.10 before 2.8.2 does not verify that the… CWE-345