---
id: "CVE-2026-14556"
kind: "vulnerability"
aliases: ["CVE-2026-14556"]
title: "HappyForms WordPress plugin: unescaped referral value injects HTML into admin emails"
severity: "medium"
cvss: 5.4
epss: 0.00155
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["happyforms", "package", "self-hosted", "wordpress"]
not_affected_if: ["patched-version", "plugin-not-installed"]
published_at: "2026-10-21T09:17:07+00:00"
first_seen_at: "2026-10-23T21:57:28+00:00"
updated_at: "2026-10-25T04:14:38+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-14556", "first_seen_at": "2026-10-23T21:57:28+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-14556", "first_seen_at": "2026-10-24T13:15:54+00:00"}]
---

# HappyForms WordPress plugin: unescaped referral value injects HTML into admin emails

The HappyForms WordPress plugin before 1.26.15 places a user-supplied referral value into form notification emails without sanitising or escaping it. An unauthenticated attacker can inject arbitrary HTML into the emails that site administrators receive.

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

## How to check

- Check the installed HappyForms version in the WordPress admin plugin list or with `wp plugin get happyforms --field=version`, and compare it against `1.26.15`.
- Look for the HappyForms plugin directory in `wp-content/plugins/` on the server.

## Fix

- Update the HappyForms plugin to `1.26.15` or later.
- If an update is not possible, disable the HappyForms plugin until it is patched.

## Timeline

- 2026-10-23T21:57:28+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-14556
- 2026-10-24T13:15:54+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-14556

## From the sources

The HappyForms WordPress plugin before 1.26.15 does not sanitise or escape a user-controlled referral value before embedding it in the form notification email, allowing unauthenticated attackers to inject arbitrary HTML into the emails site administrators receive.

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