Vulnerability-Lookup

GHSA-23J5-87FX-HGC9

Vulnerability from github – Published: 2026-02-27 06:31 – Updated: 2026-02-27 06:31

Details

The Fluent Forms Pro Add On Pack plugin for WordPress is vulnerable to Insufficient Verification of Data Authenticity in all versions up to, and including, 6.1.17. This is due to the PayPal IPN (Instant Payment Notification) verification being disabled by default (disable_ipn_verification defaults to 'yes' in PayPalSettings.php). This makes it possible for unauthenticated attackers to send forged PayPal IPN notifications to the publicly accessible IPN endpoint, marking unpaid form submissions as "paid" and triggering post-payment automation (emails, access grants, digital product delivery).

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-2428"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-345"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-02-27T04:16:03Z",
    "severity": "HIGH"
  },
  "details": "The Fluent Forms Pro Add On Pack plugin for WordPress is vulnerable to Insufficient Verification of Data Authenticity in all versions up to, and including, 6.1.17. This is due to the PayPal IPN (Instant Payment Notification) verification being disabled by default (`disable_ipn_verification` defaults to `\u0027yes\u0027` in `PayPalSettings.php`). This makes it possible for unauthenticated attackers to send forged PayPal IPN notifications to the publicly accessible IPN endpoint, marking unpaid form submissions as \"paid\" and triggering post-payment automation (emails, access grants, digital product delivery).",
  "id": "GHSA-23j5-87fx-hgc9",
  "modified": "2026-02-27T06:31:28Z",
  "published": "2026-02-27T06:31:28Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-2428"
    },
    {
      "type": "WEB",
      "url": "https://fluentforms.com/docs/changelog/#2-toc-title"
    },
    {
      "type": "WEB",
      "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/e5c62e54-da06-4b44-ba70-63065e664b0d?source=cve"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-2428 (GCVE-0-2026-2428)

Vulnerability from cvelistv5 – Published: 2026-02-27 03:23 – Updated: 2026-04-08 17:29

Title

Fluent Forms Pro Add On Pack <= 6.1.17 - Missing Authorization to Unauthenticated Payment Status modification

Summary

The Fluent Forms Pro Add On Pack plugin for WordPress is vulnerable to Insufficient Verification of Data Authenticity in all versions up to, and including, 6.1.17. This is due to the PayPal IPN (Instant Payment Notification) verification being disabled by default (`disable_ipn_verification` defaults to `'yes'` in `PayPalSettings.php`). This makes it possible for unauthenticated attackers to send forged PayPal IPN notifications to the publicly accessible IPN endpoint, marking unpaid form submissions as "paid" and triggering post-payment automation (emails, access grants, digital product delivery).

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CWE

CWE-345 - Insufficient Verification of Data Authenticity

Assigner

Wordfence

References

2 references

URL	Tags
https://www.wordfence.com/threat-intel/vulnerabil…
https://fluentforms.com/docs/changelog/#2-toc-title

Impacted products

1 product

Vendor	Product	Version
techjewel	Fluent Forms Pro Add On Pack	Affected: 0 , ≤ 6.1.17 (semver)

Credits

Prickly Cactus

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-2428",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-02-27T15:49:08.291600Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-02-27T15:49:59.392Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Fluent Forms Pro Add On Pack",
          "vendor": "techjewel",
          "versions": [
            {
              "lessThanOrEqual": "6.1.17",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Prickly Cactus"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The Fluent Forms Pro Add On Pack plugin for WordPress is vulnerable to Insufficient Verification of Data Authenticity in all versions up to, and including, 6.1.17. This is due to the PayPal IPN (Instant Payment Notification) verification being disabled by default (`disable_ipn_verification` defaults to `\u0027yes\u0027` in `PayPalSettings.php`). This makes it possible for unauthenticated attackers to send forged PayPal IPN notifications to the publicly accessible IPN endpoint, marking unpaid form submissions as \"paid\" and triggering post-payment automation (emails, access grants, digital product delivery)."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-345",
              "description": "CWE-345 Insufficient Verification of Data Authenticity",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-08T17:29:56.825Z",
        "orgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
        "shortName": "Wordfence"
      },
      "references": [
        {
          "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/e5c62e54-da06-4b44-ba70-63065e664b0d?source=cve"
        },
        {
          "url": "https://fluentforms.com/docs/changelog/#2-toc-title"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-02-12T21:03:48.000Z",
          "value": "Vendor Notified"
        },
        {
          "lang": "en",
          "time": "2026-02-26T14:33:15.000Z",
          "value": "Disclosed"
        }
      ],
      "title": "Fluent Forms Pro Add On Pack \u003c= 6.1.17 - Missing Authorization to Unauthenticated Payment Status modification"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
    "assignerShortName": "Wordfence",
    "cveId": "CVE-2026-2428",
    "datePublished": "2026-02-27T03:23:19.329Z",
    "dateReserved": "2026-02-12T20:48:34.727Z",
    "dateUpdated": "2026-04-08T17:29:56.825Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-23J5-87FX-HGC9

CVE-2026-2428 (GCVE-0-2026-2428)

Tags

Sightings

Nomenclature