---
id: "CVE-2026-109998"
kind: "vulnerability"
aliases: ["CVE-2026-109998"]
title: "Mang Board WordPress plugin: unauthenticated stored cross-site scripting via content parameter"
severity: "high"
cvss: 7.2
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["package", "php", "self-hosted", "wordpress"]
not_affected_if: ["plugin-deactivated", "plugin-not-installed"]
published_at: "2026-10-16T05:17:29+00:00"
first_seen_at: "2026-10-23T21:57:12+00:00"
updated_at: "2026-10-25T03:29:53+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-109998", "first_seen_at": "2026-10-23T21:57:12+00:00"}]
---

# Mang Board WordPress plugin: unauthenticated stored cross-site scripting via content parameter

The Mang Board WordPress plugin up to and including 2.4.3 does not sanitize the 'content' parameter, and its public AJAX endpoint wp_ajax_nopriv_mb_template returns that content as text/html. An unauthenticated attacker can store 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 plugin version in the WordPress admin plugin list or with `wp plugin get mang-board --field=version` (unknown if the plugin slug differs)
- Look for the `mb_template` AJAX action in the plugin code with `grep -r "mb_template" wp-content/plugins/`

## Fix

- Update the Mang Board plugin to a version later than `2.4.3` (the first fixed version is unknown from the sources)
- If no fixed version is available, deactivate the plugin until one is released

## Timeline

- 2026-10-23T21:57:12+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-109998

## From the sources

The Mang Board plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'content' parameter in all versions up to, and including, 2.4.3 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. This is exploitable because the wp_ajax_nopriv_mb_template endpoint is publicly accessible without authentication, nonce verification is not enforced for the content_reply mode, and admin-ajax.php responds with Content-Type: text/html, causing browsers to execute injected tags embedded in the JSON response body.

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