CVE-2026-39935
Received Received - Intake
Cross-Site Scripting in Mediawiki CampaignEvents Extension

Publication date: 2026-04-07

Last updated on: 2026-04-08

Assigner: wikimedia-foundation

Description
Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in The Wikimedia Foundation Mediawiki - CampaignEvents Extension allows Cross-Site Scripting (XSS). This issue was remediated only on the `master` branch.
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Meta Information
Published
2026-04-07
Last Modified
2026-04-08
Generated
2026-06-16
AI Q&A
2026-04-08
EPSS Evaluated
2026-06-15
NVD
CVE-2026-39935
EUVD
EUVD-2026-19980
Affected Vendors & Products
Showing 3 associated CPEs
Vendor Product Version / Range
the_wikimedia_foundation mediawiki_campaignevents_extension to 1.43.7 (inc)
the_wikimedia_foundation mediawiki_campaignevents_extension to 1.44.4 (inc)
the_wikimedia_foundation mediawiki_campaignevents_extension to 1.45.2 (inc)
Helpful Resources
Exploitability
CWE
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KEV
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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.
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Executive Summary

This vulnerability is a Cross-Site Scripting (XSS) issue caused by improper neutralization of input during web page generation in the Wikimedia Foundation Mediawiki CampaignEvents Extension. It affects versions 1.43.7, 1.44.4, and 1.45.2 of the extension.

Impact Analysis

The vulnerability allows attackers to inject malicious scripts into web pages generated by the CampaignEvents Extension. This can lead to unauthorized actions such as stealing user credentials, session hijacking, or executing malicious code in the context of the affected website.

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