CVE-2026-2428Network attack vector

Unauthenticated payment-status forgery via disabled IPN verification

Published Feb 27, 2026 · Updated Feb 27, 2026

Payment verification failure in WPManageNinja Fluent Forms Pro Add-on 6.1.17 and earlier allows remote attackers to mark unpaid submissions paid. PayPalSettings.php defaults disable_ipn_verification to yes, so the public IPN handler accepts attacker-supplied payment notifications without PayPal authenticity verification. No authentication or user interaction is required; unpaid submissions can be marked paid and post-payment email, access, or delivery automation can run.

CVSS severity7.5
High
EPSS probability0.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Payment verification failure in WPManageNinja Fluent Forms Pro Add-on 6.1.17 and earlier allows remote attackers to mark unpaid submissions paid. PayPalSettings.php defaults disable_ipn_verification to yes, so the public IPN handler accepts attacker-supplied payment notifications without PayPal authenticity verification. No authentication or user interaction is required; unpaid submissions can be marked paid and post-payment email, access, or delivery automation can run.

The record

CVE
CVE-2026-2428
Published
Feb 27, 2026
Updated
Feb 27, 2026
Vendor
Mahmudul Hasan Arif
Product
Fluent Forms Pro Add-on
Classifications
CWE-345, T1565.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 27, 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=* <=6.1.17

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mahmudul Hasan Arif · Fluent Forms Pro Add-onversion=* <=6.1.17

Published CVSS scores

7.5WordfenceCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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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