Ninja Forms <= 3.15.5 - Unauthenticated Stored Cross-Site Scripting via 'extra' Parameter via Metadata Key Normalization
Summary
| CVE | CVE-2026-109997 |
|---|---|
| State | PUBLISHED |
| Assigner | Wordfence |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-31 06:16:31 UTC |
| Updated | 2026-10-31 06:16:31 UTC |
| Description | The Ninja Forms – Contact Form Builder with Calculators, Quizzes, Signatures & AI Form Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'formData.extra' parameter in all versions up to, and including, 3.15.5 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The nf_ajax_submit endpoint issues a valid nonce to any requester on failure, effectively neutralizing the nonce check and making exploitation trivially achievable in a single unauthenticated request. |
Risk And Classification
Primary CVSS: v3.1 7.2 HIGH from [email protected]
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
Problem Types: CWE-79 | CWE-79 CWE-79 Improper Neutralization of Input During Web Page Generation
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Primary | 7.2 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
| 3.1 | CNA | DECLARED | 7.2 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
ChangedConfidentiality
LowIntegrity
LowAvailability
NoneCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Kstover | Ninja Forms Contact Form Builder With Calculators Quizzes Signatures AI Form Builder | affected 3.15.5 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| plugins.trac.wordpress.org/browser/ninja-forms/tags/3.15.5/includes/AJAX/Controllers/Sub... | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/ninja-forms/tags/3.15.5/includes/Admin/Metaboxes/Calc... | [email protected] | plugins.trac.wordpress.org | |
| www.wordfence.com/threat-intel/vulnerabilities/id/54da4deb-e50c-478d-ab99-222c5... | [email protected] | www.wordfence.com | |
| plugins.trac.wordpress.org/changeset/3749135/ninja-forms/trunk/includes/Templates/admin-... | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/ninja-forms/tags/3.15.5/includes/Templates/admin-meta... | [email protected] | plugins.trac.wordpress.org | |
| wordpress.org/plugins/ninja-forms | [email protected] | wordpress.org | |
| plugins.trac.wordpress.org/browser/ninja-forms/tags/3.15.5/includes/Database/Models/Subm... | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/ninja-forms/tags/3.15.5/includes/Actions/Save.php | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/ninja-forms/tags/3.15.5/includes/AJAX/Controllers/Sub... | [email protected] | plugins.trac.wordpress.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: daroo (en)
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-10-13T13:50:21.000Z | Vendor Notified |
| CNA | 2026-10-30T17:25:04.000Z | Disclosed |
There are currently no legacy QID mappings associated with this CVE.