CVE-2026-100376

Received Received - Intake

Stored XSS in MediaWiki TemplateSandbox Extension

Publication date: 2026-09-25

Last updated on: 2026-09-25

Assigner: wikimedia-foundation

Description

Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Wikimedia Foundation Mediawiki - TemplateSandbox Extension allows Cross-Site Scripting (XSS). This issue affects Mediawiki - TemplateSandbox Extension: from * before 1.46.1, 1.45.5, 1.43.10.

CVSS Scores

EPSS Scores

Probability:
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Meta Information

Published

2026-09-25

Last Modified

2026-09-25

Generated

2026-09-26

AI Q&A

2026-09-26

EPSS Evaluated

N/A

NVD

CVE-2026-100376

Affected Vendors & Products

Vendor	Product	Version / Range
wikimedia_foundation	mediawiki_template_sandbox_extension	From 1.43.10 (inc) to 1.46.1 (exc)
wikimedia_foundation	mediawiki_template_sandbox_extension	1.45.5

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-79	The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

Attack-Flow Graph

Executive Summary

This vulnerability is an XSS issue in the Wikimedia Foundation MediaWiki TemplateSandbox Extension. It allows attackers to inject malicious scripts into web pages viewed by other users due to improper neutralization of input during web page generation.

Impact Analysis

An attacker could exploit this to steal user sessions, deface web pages, or perform actions on behalf of users. It may lead to unauthorized data access or manipulation if users interact with the compromised pages.

Compliance Impact

This XSS vulnerability could lead to data breaches, violating GDPR's integrity and confidentiality requirements or HIPAA's safeguards for protected health information. Organizations may face compliance penalties if user data is compromised.

Mitigation Strategies

Update Mediawiki - TemplateSandbox Extension to version 1.46.1, 1.45.5, or 1.43.10 or later to address the XSS vulnerability.

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