---
id: "CVE-2026-93766"
page: "https://infrastack.ai/live/CVE-2026-93766"
kind: "vulnerability"
aliases: ["CVE-2026-93766"]
title: "Happyforms Pro WordPress plugin: stored script injection via referer field"
severity: "high"
cvss: 7.2
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["happyforms-pro", "package", "self-hosted", "wordpress"]
not_affected_if: ["newer-version", "plugin-not-installed"]
published_at: "2026-11-07T12:17:47+00:00"
first_seen_at: "2026-11-07T12:47:09+00:00"
updated_at: "2026-11-07T12:48:44+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-93766", "first_seen_at": "2026-11-07T12:47:09+00:00"}]
exploit_sources: []
---

# Happyforms Pro WordPress plugin: stored script injection via referer field

Link for people: https://infrastack.ai/live/CVE-2026-93766 (this .md is for agents)

The Happyforms Pro plugin for WordPress fails to sanitize the happyforms_client_referer parameter, so unauthenticated visitors can store scripts that run in pages. An attacker gets script execution in the browser of anyone who opens an affected page, including logged-in site administrators.

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

## How to check

- Check the installed Happyforms Pro plugin version in the WordPress admin under Plugins; affected versions are all up to and including `1.38.9`.
- Search form submission data and page content for unexpected script tags.

## Fix

- Happyforms Pro: unknown; the sources do not state a fixed version.

## Timeline

- 2026-11-07T12:47:09+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-93766

## From the sources

The Happyforms Pro plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'happyforms_client_referer' parameter in all versions up to, and including, 1.38.9 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.

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