---
id: CVE-2026-100383
title: >-
  Improper Neutralization of Input During Web Page Generation (XSS or
  'Cross-site Scripting') vulnerability in Wikimedia Foundation Mediawiki -
  WikiLambda Extension allows Cross-Site Scripting (XSS).


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


  This issue affects Mediawiki - WikiLam…
severity: medium
cvss: 4.8
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N'
cwe:
  - CWE-79
vendor: Wikimedia Foundation
product: Mediawiki - WikiLambda Extension
affected:
  - mediawiki_-_wikilambda_extension 1.47.0-alpha
published: '2026-09-25'
updated: '2026-09-25'
sourceUpdated: '2026-09-25T22:17:10.303'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100383'
references:
  - url: 'https://gerrit.wikimedia.org/r/c/mediawiki/extensions/WikiLambda/+/1326391'
    label: c4f26cc8-17ff-4c99-b5e2-38fc1793eacc
  - url: 'https://phabricator.wikimedia.org/T434967'
    label: c4f26cc8-17ff-4c99-b5e2-38fc1793eacc
tags:
  - nvd
  - cve.org
cvssSource: cna
ingestedAt: '2026-09-25T21:19:40.218Z'
---

## Overview

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

This issue affects Mediawiki - WikiLambda Extension: 1.47.0-alpha. The issue has been remediated on the `master` branch.

## Remediation

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