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Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Wikimedia Foundation Mediawiki -… (CVE-2026-100383)

0
Medium
Published: 09/26/2026 (09/26/2026, 00:32:18 UTC)
Source: GCVE Database

Description

A Cross-Site Scripting (XSS) vulnerability exists in the Wikimedia Foundation Mediawiki WikiLambda Extension version 1.47.0-alpha due to improper neutralization of input during web page generation. This vulnerability has been fixed in the master branch of the codebase. No known exploits are reported in the wild. The vulnerability is rated medium severity based on the available information.

CVSS v4.0

Attack Vector
Network
Attack Complexity
Low
Attack Requirements
None
Privileges Required
High
User Interaction
Passive
Vuln. Confidentiality
Low
Vuln. Integrity
None
Vuln. Availability
None
Subsq. Confidentiality
None
Subsq. Integrity
None
Subsq. Availability
None
Scope
X
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected software

GitHub Actionsmore threats →ai
wikimedia/extensions/WikiLambda
pkg:github/wikimedia/extensions/WikiLambda
Affected versions
=1.47.0-alpha

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AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 09/26/2026, 04:58:49 UTC

Technical Analysis

The vulnerability identified as CVE-2026-100383 affects the Wikimedia Foundation Mediawiki WikiLambda Extension version 1.47.0-alpha. It is an improper neutralization of input during web page generation, leading to Cross-Site Scripting (XSS). The issue has been remediated in the master branch, indicating a fix is available but no specific patch version is stated. The CVSS vector indicates network attack vector, low complexity, and privileges required, with user interaction needed and low impact on confidentiality. No known active exploitation is reported.

Potential Impact

Successful exploitation could allow an attacker with high privileges and user interaction to execute malicious scripts in the context of the affected web application, potentially leading to limited confidentiality impact. However, no active exploitation in the wild has been reported.

Mitigation Recommendations

The vulnerability has been remediated in the master branch of the Mediawiki WikiLambda Extension. Users should update to the fixed version once it is officially released. Until then, monitor the official Wikimedia Foundation advisories for patch availability. No additional vendor advisory or patch links are provided, so check the Wikimedia Foundation's official channels for updates.

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Technical Details

Gcve Source
db.gcve.eu
Osv Id
GHSA-45r6-8hjm-wh6p
Osv Schema Version
1.4.0
Aliases
["CVE-2026-100383"]
Database Specific Severity
MODERATE
Cvss Version
4.0
State
PUBLISHED

Threat ID: 6ab74f35f7a7c54106e138cc

Added to database: 09/26/2026, 04:51:01 UTC

Last enriched: 09/26/2026, 04:58:49 UTC

Last updated: 09/27/2026, 02:47:33 UTC

Views: 15

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