Vulnerability-Lookup

GHSA-XC8Q-RH3X-H9M3

Vulnerability from github – Published: 2026-03-13 21:31 – Updated: 2026-03-13 21:31

Details

The Formidable Forms plugin for WordPress is vulnerable to an authorization bypass through user-controlled key in all versions up to, and including, 6.28. This is due to the frm_strp_amount AJAX handler (update_intent_ajax) overwriting the global $_POST data with attacker-controlled JSON input and then using those values to recalculate payment amounts via field shortcode resolution in generate_false_entry(). The handler relies on a nonce that is publicly exposed in the page's JavaScript (frm_stripe_vars.nonce), which provides CSRF protection but not authorization. This makes it possible for unauthenticated attackers to manipulate PaymentIntent amounts before payment completion on forms using dynamic pricing with field shortcodes, effectively paying a reduced amount for goods or services.

Severity ?

5.3 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-2888"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-639"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-03-13T19:54:34Z",
    "severity": "MODERATE"
  },
  "details": "The Formidable Forms plugin for WordPress is vulnerable to an authorization bypass through user-controlled key in all versions up to, and including, 6.28. This is due to the `frm_strp_amount` AJAX handler (`update_intent_ajax`) overwriting the global `$_POST` data with attacker-controlled JSON input and then using those values to recalculate payment amounts via field shortcode resolution in `generate_false_entry()`. The handler relies on a nonce that is publicly exposed in the page\u0027s JavaScript (`frm_stripe_vars.nonce`), which provides CSRF protection but not authorization. This makes it possible for unauthenticated attackers to manipulate PaymentIntent amounts before payment completion on forms using dynamic pricing with field shortcodes, effectively paying a reduced amount for goods or services.",
  "id": "GHSA-xc8q-rh3x-h9m3",
  "modified": "2026-03-13T21:31:47Z",
  "published": "2026-03-13T21:31:46Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-2888"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/formidable/tags/6.28/stripe/controllers/FrmStrpLiteHooksController.php#L88"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/formidable/tags/6.28/stripe/models/FrmStrpLiteAuth.php#L322"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/formidable/tags/6.28/stripe/models/FrmStrpLiteAuth.php#L402"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/changeset?sfp_email=\u0026sfph_mail=\u0026reponame=\u0026new=3480574%40formidable%2Ftrunk\u0026old=3460198%40formidable%2Ftrunk\u0026sfp_email=\u0026sfph_mail="
    },
    {
      "type": "WEB",
      "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/b8be3b6e-a035-4e6f-ba2b-ce9e59ebf2e0?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:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-2888 (GCVE-0-2026-2888)

Vulnerability from cvelistv5 – Published: 2026-03-13 08:25 – Updated: 2026-03-13 16:04

Title

Formidable Forms <= 6.28 - Unauthenticated Payment Amount Manipulation via 'item_meta' Parameter

Summary

The Formidable Forms plugin for WordPress is vulnerable to an authorization bypass through user-controlled key in all versions up to, and including, 6.28. This is due to the `frm_strp_amount` AJAX handler (`update_intent_ajax`) overwriting the global `$_POST` data with attacker-controlled JSON input and then using those values to recalculate payment amounts via field shortcode resolution in `generate_false_entry()`. The handler relies on a nonce that is publicly exposed in the page's JavaScript (`frm_stripe_vars.nonce`), which provides CSRF protection but not authorization. This makes it possible for unauthenticated attackers to manipulate PaymentIntent amounts before payment completion on forms using dynamic pricing with field shortcodes, effectively paying a reduced amount for goods or services.

Severity ?

5.3 (Medium)


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

CWE

CWE-639 - Authorization Bypass Through User-Controlled Key

Assigner

Wordfence

References

URL

Tags

	https://www.wordfence.com/threat-intel/vulnerabil…
	https://plugins.trac.wordpress.org/browser/formid…
	https://plugins.trac.wordpress.org/browser/formid…
	https://plugins.trac.wordpress.org/browser/formid…
	https://plugins.trac.wordpress.org/changeset?sfp_…

Impacted products

	Vendor	Product	Version
	strategy11team	Formidable Forms – Contact Form Plugin, Survey, Quiz, Payment, Calculator Form & Custom Form Builder	Affected: * , ≤ 6.28 (semver)

Credits

Michael Iden

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-2888",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-13T16:04:01.348416Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-03-13T16:04:08.409Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Formidable Forms \u2013 Contact Form Plugin, Survey, Quiz, Payment, Calculator Form \u0026 Custom Form Builder",
          "vendor": "strategy11team",
          "versions": [
            {
              "lessThanOrEqual": "6.28",
              "status": "affected",
              "version": "*",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Michael Iden"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The Formidable Forms plugin for WordPress is vulnerable to an authorization bypass through user-controlled key in all versions up to, and including, 6.28. This is due to the `frm_strp_amount` AJAX handler (`update_intent_ajax`) overwriting the global `$_POST` data with attacker-controlled JSON input and then using those values to recalculate payment amounts via field shortcode resolution in `generate_false_entry()`. The handler relies on a nonce that is publicly exposed in the page\u0027s JavaScript (`frm_stripe_vars.nonce`), which provides CSRF protection but not authorization. This makes it possible for unauthenticated attackers to manipulate PaymentIntent amounts before payment completion on forms using dynamic pricing with field shortcodes, effectively paying a reduced amount for goods or services."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-639",
              "description": "CWE-639 Authorization Bypass Through User-Controlled Key",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-03-13T08:25:17.249Z",
        "orgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
        "shortName": "Wordfence"
      },
      "references": [
        {
          "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/b8be3b6e-a035-4e6f-ba2b-ce9e59ebf2e0?source=cve"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/formidable/tags/6.28/stripe/models/FrmStrpLiteAuth.php#L322"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/formidable/tags/6.28/stripe/models/FrmStrpLiteAuth.php#L402"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/formidable/tags/6.28/stripe/controllers/FrmStrpLiteHooksController.php#L88"
        },
        {
          "url": "https://plugins.trac.wordpress.org/changeset?sfp_email=\u0026sfph_mail=\u0026reponame=\u0026new=3480574%40formidable%2Ftrunk\u0026old=3460198%40formidable%2Ftrunk\u0026sfp_email=\u0026sfph_mail="
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-03-12T19:24:45.000Z",
          "value": "Disclosed"
        }
      ],
      "title": "Formidable Forms \u003c= 6.28 - Unauthenticated Payment Amount Manipulation via \u0027item_meta\u0027 Parameter"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
    "assignerShortName": "Wordfence",
    "cveId": "CVE-2026-2888",
    "datePublished": "2026-03-13T08:25:17.249Z",
    "dateReserved": "2026-02-20T17:11:27.201Z",
    "dateUpdated": "2026-03-13T16:04:08.409Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

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-XC8Q-RH3X-H9M3

CVE-2026-2888 (GCVE-0-2026-2888)

Tags

Sightings

Nomenclature