---
id: "CVE-2026-110899"
kind: "vulnerability"
aliases: ["CVE-2026-110899"]
title: "Ninja Forms WordPress plugin: stored XSS through form input up to 3.15.5"
severity: "high"
cvss: 7.1
epss: 0.00146
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["ninja-forms", "package", "self-hosted", "wordpress"]
not_affected_if: ["plugin-not-installed"]
published_at: "2026-10-21T08:16:42+00:00"
first_seen_at: "2026-10-23T21:57:28+00:00"
updated_at: "2026-10-25T03:31:56+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-110899", "first_seen_at": "2026-10-23T21:57:28+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-110899", "first_seen_at": "2026-10-24T13:15:54+00:00"}]
---

# Ninja Forms WordPress plugin: stored XSS through form input up to 3.15.5

Ninja Forms, a WordPress form-builder plugin, does not neutralize some input before rendering it on a page, so the input is stored and shown to other visitors. An attacker can run scripts in the browser of anyone who views the affected page, such as an admin.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed Ninja Forms plugin version in the WordPress admin under Plugins, or with `wp plugin get ninja-forms --field=version`
- Compare the version against `3.15.5`; versions up to and including it are listed as affected

## Fix

- Update Ninja Forms to a version newer than `3.15.5` (the advisory does not name the fixed release; unknown)

## Timeline

- 2026-10-23T21:57:28+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-110899
- 2026-10-24T13:15:54+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-110899

## From the sources

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Kevin Stover Ninja Forms ninja-forms allows Stored XSS.This issue affects Ninja Forms: from n/a through 3.15.5.

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