CVE-2026-100155
Ninja Forms <= 3.15.5 - Unauthenticated Arbitrary Shortcode Execution via 'formData' Field Value via Success Message Merge Tag
The The Ninja Forms – Contact Form Builder with Calculators, Quizzes, Signatures & AI Form Builder plugin for WordPress is vulnerable to arbitrary shortcode execution in all versions up to, and including, 3.15.5 This is due to the software allowing users to execute an action that does not properly validate a value before running do_shortcode. This makes it possible for unauthenticated attackers to execute arbitrary shortcodes.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| Ninja Forms – Contact Form Builder with Calculators, Quizzes, Signatures & AI Form Builder kstover |
≥ 0; ≤ 3.15.5 (affected, semver)
Other versions: unaffected |
CNA: Wordfence |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 6.5 medium |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N | CNA: Wordfence |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://www.wordfence.com/threat-intel/vulnerabilities/id/a1cf42f7-77c6-4594-a6a4-cebf5c3558d7?source=cveCNA: Wordfence
- https://plugins.trac.wordpress.org/browser/ninja-forms/tags/3.15.4/includes/Actions/SuccessMessage.php#L63CNA: Wordfence
- https://plugins.trac.wordpress.org/browser/ninja-forms/tags/3.15.4/includes/Actions/SuccessMessage.php#L70CNA: Wordfence
- https://plugins.trac.wordpress.org/browser/ninja-forms/tags/3.15.4/includes/AJAX/Controllers/Submission.php#L52CNA: Wordfence
- https://plugins.trac.wordpress.org/browser/ninja-forms/tags/3.15.4/includes/Abstracts/MergeTags.php#L64CNA: Wordfence
- https://plugins.trac.wordpress.org/browser/ninja-forms/tags/3.15.4/includes/MergeTags/Fields.php#L268CNA: Wordfence
- https://plugins.trac.wordpress.org/browser/ninja-forms/tags/3.15.4/includes/AJAX/Controllers/Submission.php#L60CNA: Wordfence
- https://wordpress.org/plugins/ninja-forms/CNA: Wordfence
- https://plugins.trac.wordpress.org/changeset?reponame=&new=3749135%40ninja-forms%2Ftags%2F3.15.6&old=3717122%40ninja-forms%2Ftags%2F3.15.5CNA: Wordfence
For agents and automation
Read public disclosures for free as Markdown or JSON. Compatible browsers also expose native WebMCP tools to search disclosures, read this page, and discover API access.
Use the ontology-linked Cyber API with x402 pay per request, or a Y2 Pro or Elite API key with the intel:cyber scope.
Endpoints and access details
https://api.y2.dev/api/v2/cyber/cveshttps://api.y2.dev/api/v2/cyber/cves/{cveId}
A workspace owner or admin can create a Pro or Elite API key. Send Authorization: Bearer <Y2_API_KEY> from your trusted agent runtime.
For x402, omit Authorization and read the HTTP 402 payment challenge before signing a retry. Public browser tools do not make payments.