Is CVE-2026-4406 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-4406 being exploited in the wild.

How severe is CVE-2026-4406?

Medium severity, with a CVSS score of 4.7, published 8 April 2026.

Which products and versions are affected?

Gravity Forms Gravity Forms <= 2.9.30.

Is there a fix for CVE-2026-4406?

A patch was published on 2026-04-02: Fixed in version 2.9.31 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-4406 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-4406?

Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-4406: Gravity Forms Reflected XSS in gform_get_config AJAX action

Q: Is there a fix for CVE-2026-4406?

A patch was published on 2026-04-02: Fixed in version 2.9.31 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-4406 attacked?

It is attacked over the network, in a software library.

Q: Am I affected by CVE-2026-4406?

Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-4406 · Severity: medium · CVSS 4.7 · Published 2026-04-08

Gravity Forms is a popular WordPress plugin used to create and manage web forms. A security vulnerability allows unauthenticated attackers to inject malicious scripts into a web page if they can trick a user into clicking a specific link. While this cannot be used to directly steal data from logged-in users, it can be used to alter the appearance of the page or redirect visitors to malicious sites.

Quick answers

Is CVE-2026-4406 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-4406 being exploited in the wild.
How severe is CVE-2026-4406?: Medium severity, with a CVSS score of 4.7, published 8 April 2026.
Which products and versions are affected?: Gravity Forms Gravity Forms <= 2.9.30.
Is there a fix for CVE-2026-4406?: A patch was published on 2026-04-02: Fixed in version 2.9.31 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-4406 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-4406?: Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability is a Reflected Cross-Site Scripting (XSS) flaw within the `gform_get_config` AJAX action. The root cause is the `GFCommon::send_json()` method, which outputs JSON-encoded data wrapped in HTML comment delimiters using `echo` and `wp_die()`, causing the browser to interpret the response as `text/html` instead of `application/json`. Because `wp_json_encode()` does not escape angle brackets, an attacker can inject script tags into the `form_ids` array. Exploitation requires a valid `config_nonce`, which is publicly accessible on any page rendering a form and remains valid for 12 hours. An unauthenticated attacker can execute arbitrary JavaScript in the context of a victim's browser via a crafted link, though the impact is limited to unauthenticated sessions. The issue was addressed in version 2.9.31.

Affected products

Gravity Forms Gravity Forms <= 2.9.30

Timeline

2026-03-19: other: Last vulnerable version (2.9.30) released
2026-04-02: patched: Fixed in version 2.9.31
2026-04-08: disclosed: CVE published

References

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