CVE-2026-4406

What it is

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.

At a glance

Exploitability

Can be exploited over the network without logging in, but needs a user to act. Limited direct impact.

Exploit odds

0.4% chance of exploitation in the next 30 days (EPSS).

Fix

No patch or advisory is linked yet. Look at mitigations or restrict exposure.

Timeline

1. 2026-04-08 00:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-07-24 23:10 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.4% in the next 30 days (EPSS).
• Severity: 4.7 MEDIUM (CVSS).
• Fix: none linked yet, which raises it.

Details

Published

2026-04-08 00:16 UTC

Last modified

2026-07-24 23:10 UTC

Exploit probability

0.4% · EPSS, next 30 days

Weakness

CWE-79 · Cross-site scripting

Record status

Deferred

Attack profile CVSS 3.1 · 4.7

Attack vector

Network

Complexity

High

Privileges needed

None

User interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-4406.md and follow it. Check whether this project is affected by CVE-2026-4406. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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