---
id: CVE-2026-4406
title: >-
  The Gravity Forms plugin for WordPress is vulnerable to Reflected Cross-Site
  Scripting via the `form_ids` parameter in the `gform_get_config` AJAX action
  in all versions up to, and including, 2.9.30
summary: >-
  The Gravity Forms plugin for WordPress is vulnerable to Reflected Cross-Site
  Scripting via the `form_ids` parameter in the `gform_get_config` AJAX action
  in all versions up to, and including, 2.9.30. This is due to the
  `GFCommon::send_js…
severity: medium
cvss: 4.7
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N'
cwe:
  - CWE-79
published: '2026-04-08'
updated: '2026-07-24'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-4406'
references:
  - url: 'https://docs.gravityforms.com/gravityforms-change-log/'
    label: security@wordfence.com
  - url: >-
      https://plugins.trac.wordpress.org/browser/gravityforms/trunk/common.php#L8267
    label: security@wordfence.com
  - url: >-
      https://plugins.trac.wordpress.org/browser/gravityforms/trunk/includes/config/class-gf-config-collection.php#L56
    label: security@wordfence.com
  - url: >-
      https://plugins.trac.wordpress.org/browser/gravityforms/trunk/includes/config/class-gf-config-service-provider.php#L144
    label: security@wordfence.com
  - url: >-
      https://plugins.trac.wordpress.org/browser/gravityforms/trunk/includes/config/items/class-gf-config-global.php#L22
    label: security@wordfence.com
  - url: >-
      https://www.wordfence.com/threat-intel/vulnerabilities/id/4126d452-65a9-48f5-a3f5-5be1b8fff80c?source=cve
    label: security@wordfence.com
tags:
  - nvd
  - exploit-available
epss: 0.00387
epssPercentile: 0.30043
ingestedAt: '2026-07-25T23:05:58.388Z'
exploits:
  github: 1
  githubRepos:
    - 'https://github.com/Hann1bl3L3ct3r/CVE-2026-4406'
  checkedAt: '2026-09-26T09:05:44.187Z'
exploitAvailable: true
---

## Overview

The Gravity Forms plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the `form_ids` parameter in the `gform_get_config` AJAX action in all versions up to, and including, 2.9.30. This is due to the `GFCommon::send_json()` method outputting JSON-encoded data wrapped in HTML comment delimiters using `echo` and `wp_die()`, which serves the response with a `Content-Type: text/html` header instead of `application/json`. The `wp_json_encode()` function does not HTML-encode angle brackets within JSON string values, allowing injected HTML/script tags in `form_ids` array values to be parsed and executed by the browser. The required `config_nonce` is generated with `wp_create_nonce('gform_config_ajax')` and is publicly embedded on every page that renders a Gravity Forms form, making it identical for all unauthenticated visitors within the same 12-hour nonce tick. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. This vulnerability cannot be exploited against users who are authenticated on the target system, but could be used to alter the target page.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.