---
id: CVE-2026-88824
title: >-
  The Master Blocks  WordPress plugin before 1.5.0 does not have authorisation
  on one of its REST routes, allowing unauthenticated users to update its
  settings, including a value that is output unescaped in the admin area,
  leading to Store…
summary: >-
  The Master Blocks  WordPress plugin before 1.5.0 does not have authorisation
  on one of its REST routes, allowing unauthenticated users to update its
  settings, including a value that is output unescaped in the admin area,
  leading to Store…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-79
product: Master Blocks
affected:
  - master_blocks >= 1.4.1 < 1.5.0
published: '2026-09-19'
updated: '2026-09-21'
sourceUpdated: '2026-09-21T13:34:57.127'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-88824'
references:
  - url: 'https://wpscan.com/vulnerability/898fda0a-4d27-4def-ae6f-35bf25a8ae8d/'
    label: contact@wpscan.com
tags:
  - nvd
  - cve.org
epss: 0.00505
epssPercentile: 0.40585
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-19T13:12:08.510452Z'
ingestedAt: '2026-09-19T06:59:13.113Z'
---

## Overview

The Master Blocks  WordPress plugin before 1.5.0 does not have authorisation on one of its REST routes, allowing unauthenticated users to update its settings, including a value that is output unescaped in the admin area, leading to Stored XSS that executes in the session of any administrator visiting a wp-admin page.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.