Threat intelligence

Contact Form 7 – PayPal & Stripe Add-on <= 2.4.9 - Unauthenticated Payment Bypass via Insufficient Verification of Data Authenticity via PayPal IPN Handler ('invoice'/'mc_gross' Verification)

CVE-2026-9189 · contact-form-7-paypal-add-on

Important: Seeing this vulnerability listed does not mean your website is affected. Exposure depends on whether you run Contact Form 7 Paypal Add On at a vulnerable version. How SiteRespond intelligence works

Vulnerability: Contact Form 7 – PayPal & Stripe Add-on <= 2.4.9 - Unauthenticated Payment Bypass via Insufficient Verification of Data Authenticity via PayPal IPN Handler ('invoice'/'mc_gross' Verification)
Affected software: contact-form-7-paypal-add-on(Plugin)
Affected versions: ≤ 2.4.9
Authentication: Unauthenticated
Vulnerability type: Other
CVE: CVE-2026-9189
Published: 28 May 2026
CISA KEV: Not listed in CISA KEV at last catalog refresh
Impact: This advisory describes a other issue in the affected software. Review the source advisory and your installed version to assess exposure.
Source: Data imported from Wordfence Intelligence (advisory 5e274781-1c20-4224-bc10-26dadb9b1e07). Methodology and redistribution notes

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