{"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":0.00356,"epssPercentile":0.29425,"ingestedAt":"2026-07-25T23:05:58.388Z","exploits":{"github":1,"githubRepos":["https://github.com/Hann1bl3L3ct3r/CVE-2026-4406"],"checkedAt":"2026-09-24T07:53:03.689Z"},"exploitAvailable":true,"slug":"CVE-2026-4406","body":"## Overview\n\nThe 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":38,"depthScoreParts":{"impact":25.9,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[{"seq":5223,"id":"CVE-2026-4406","ts":1788887254267,"field":"exploit_available","old":"false","new":"true"},{"seq":4106,"id":"CVE-2026-4406","ts":1788886370144,"field":"exploit_available","old":"true","new":"false"},{"seq":2882,"id":"CVE-2026-4406","ts":1788883036467,"field":"exploit_available","old":"false","new":"true"},{"seq":1911,"id":"CVE-2026-4406","ts":1788882439553,"field":"exploit_available","old":"true","new":"false"},{"seq":1000,"id":"CVE-2026-4406","ts":1788881873844,"field":"exploit_available","old":"false","new":"true"}]}