---
id: "CVE-2026-96660"
kind: "vulnerability"
aliases: ["CVE-2026-96660"]
title: "WordPress User Registration plugin: unauthenticated stored XSS via checkbox field"
severity: "high"
cvss: 7.2
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["package", "self-hosted", "wordpress", "wordpress-plugin"]
not_affected_if: ["plugin-not-installed", "version-above-5.2.8"]
published_at: "2026-10-17T04:17:10+00:00"
first_seen_at: "2026-10-23T21:57:14+00:00"
updated_at: "2026-10-25T03:29:28+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-96660", "first_seen_at": "2026-10-23T21:57:14+00:00"}]
---

# WordPress User Registration plugin: unauthenticated stored XSS via checkbox field

The User Registration & Membership WordPress plugin up to and including 5.2.8 does not sanitize or escape checkbox field values. An unauthenticated attacker can store a script that runs in the browser of any user who opens the injected page.

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

## How to check

- Check the installed version of the User Registration & Membership plugin in the WordPress admin Plugins screen, or with `wp plugin get user-registration --field=version`
- Confirm the version is `5.2.8` or lower to be exposed

## Fix

- Update the User Registration & Membership plugin to a version later than `5.2.8` once the vendor publishes a fixed release (unknown from sources)
- Until patched, consider disabling the plugin or restricting its registration form endpoint at the web server

## Timeline

- 2026-10-23T21:57:14+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-96660

## From the sources

The User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Checkbox Field Value in all versions up to, and including, 5.2.8 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 nopriv AJAX action user_registration_user_form_submit reaches ur_process_registration() without nonce validation, meaning any unauthenticated request can reach the vulnerable code path.

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