---
id: CVE-2026-103439
title: >-
  Improper neutralization of Script-Related HTML tags in a web page (basic XSS)
  vulnerability in The Wikimedia Foundation MediaWiki Wikbase extension allows
  Cross-Site Scripting (XSS).


  This issue affects MediaWiki Wikbase extension: 1.46,…
summary: >-
  Improper neutralization of Script-Related HTML tags in a web page (basic XSS)
  vulnerability in The Wikimedia Foundation MediaWiki Wikbase extension allows
  Cross-Site Scripting (XSS).


  This issue affects MediaWiki Wikbase extension: 1.46,…
severity: low
cvss: 0.3
cvssVector: >-
  CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:P/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L/E:P/S:N/AU:Y/R:U/V:D/RE:M/U:Amber
cwe:
  - CWE-80
vendor: The Wikimedia Foundation
product: MediaWiki Wikbase extension
affected:
  - mediawiki_wikbase_extension 1.46
  - mediawiki_wikbase_extension 1.45
  - mediawiki_wikbase_extension 1.43
published: '2026-09-30'
updated: '2026-09-30'
sourceUpdated: '2026-09-30T21:17:08.833'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-103439'
references:
  - url: 'https://gerrit.wikimedia.org/r/q/Ie7a35b211565148e0cae437a4a8c41633b81f1b3'
    label: c4f26cc8-17ff-4c99-b5e2-38fc1793eacc
  - url: 'https://phabricator.wikimedia.org/T182213'
    label: c4f26cc8-17ff-4c99-b5e2-38fc1793eacc
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-30T18:12:13.696391Z'
cvssSource: cna
ingestedAt: '2026-09-30T18:17:24.541Z'
---

## Overview

Improper neutralization of Script-Related HTML tags in a web page (basic XSS) vulnerability in The Wikimedia Foundation MediaWiki Wikbase extension allows Cross-Site Scripting (XSS).

This issue affects MediaWiki Wikbase extension: 1.46, 1.45, and 1.43.

## Remediation

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