---
id: CVE-2026-100243
title: >-
  Improper Neutralization of Input During Web Page Generation (XSS or
  'Cross-site Scripting') vulnerability in Wikimedia Foundation Mediawiki -
  WikiSEO Extension allows Stored XSS.


  This issue affects Mediawiki - WikiSEO Extension: from * …
summary: >-
  Improper Neutralization of Input During Web Page Generation (XSS or
  'Cross-site Scripting') vulnerability in Wikimedia Foundation Mediawiki -
  WikiSEO Extension allows Stored XSS.


  This issue affects Mediawiki - WikiSEO Extension: from * …
severity: medium
cvss: 6.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N'
cwe:
  - CWE-79
vendor: Wikimedia Foundation
product: Mediawiki - WikiSEO Extension
affected:
  - 'mediawiki_-_wikiseo_extension < 1.46.1, 1.45.5, 1.43.10'
published: '2026-09-29'
updated: '2026-09-30'
sourceUpdated: '2026-09-30T21:16:53.297'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100243'
references:
  - url: 'https://gerrit.wikimedia.org/r/q/Iff6ef320017649750e5c6723a91ee298eb97a408'
    label: c4f26cc8-17ff-4c99-b5e2-38fc1793eacc
  - url: 'https://phabricator.wikimedia.org/T430896'
    label: c4f26cc8-17ff-4c99-b5e2-38fc1793eacc
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-30T20:44:39.532343Z'
epss: 0.00155
epssPercentile: 0.04532
ingestedAt: '2026-09-29T17:41:02.201Z'
---

## Overview

Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Wikimedia Foundation Mediawiki - WikiSEO Extension allows Stored XSS.

This issue affects Mediawiki - WikiSEO Extension: from * before 1.46.1, 1.45.5, 1.43.10.

## Remediation

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