CVE-2026-9189Network attack vector

Unauthenticated payment bypass via unchecked PayPal IPN fields

Published May 29, 2026 · Updated May 29, 2026

Payment bypass in Contact Form 7 – PayPal & Stripe Add-on 2.4.9 and earlier allows remote attackers to complete orders through PayPal IPN. After PayPal authenticates the notification, cf7pp_paypal_ipn_handler() passes its invoice to cf7pp_complete_payment() without matching the amount, currency, or recipient to the stored order. A minimal legitimate PayPal payment is required, but it can complete a higher-value pending order without the required payment.

CVSS severity5.3
Medium
EPSS probability0.20%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Payment bypass in Contact Form 7 – PayPal & Stripe Add-on 2.4.9 and earlier allows remote attackers to complete orders through PayPal IPN. After PayPal authenticates the notification, cf7pp_paypal_ipn_handler() passes its invoice to cf7pp_complete_payment() without matching the amount, currency, or recipient to the stored order. A minimal legitimate PayPal payment is required, but it can complete a higher-value pending order without the required payment.

The record

CVE
CVE-2026-9189
Published
May 29, 2026
Updated
May 29, 2026
Vendor
Scott Paterson
Product
Contact Form 7 – PayPal & Stripe Add-on
Classifications
CWE-345, T1565.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 29, 2026CVE publishedPublication date reported by the CVE source.
  2. May 29, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=2.4.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Scott Paterson · Contact Form 7 – PayPal & Stripe Add-onversion=0 <=2.4.9

Published CVSS scores

5.3Positive TechnologiesCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-345Insufficient Verification of Data Authenticity
T1565.001Stored Data Manipulation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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