CVE-2026-39838 - Vulnerability Details - OpenCVE

Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Wikimedia Foundation MediaWiki - ProofreadPage Extension allows XSS Targeting Non-Script Elements.This issue affects .

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact Low

Vulnerable System Integrity Impact Low

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact Low

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation poc

Automatable no

Technical Impact partial

No data.

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://gerrit.wikimedia.org/r/q/Idd51e18479b32b7176b43ff74ca1c49d6bdd0628
https://phabricator.wikimedia.org/T406088

History

Tue, 07 Apr 2026 21:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Tue, 07 Apr 2026 20:45:00 +0000

Type	Values Removed	Values Added
Description		Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Wikimedia Foundation MediaWiki - ProofreadPage Extension allows XSS Targeting Non-Script Elements.This issue affects .
Title		ProofreadPage improperly sanitizes multiline styles using Sanitizer::checkCSS
Weaknesses		CWE-79
References		https://gerrit.wikimedia.org/r/q/Idd51e18479b32b7176b43ff74ca1c49d6bdd0628 https://phabricator.wikimedia.org/T406088
Metrics		cvssV4_0 `{'score': 6.9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:N/SA:N'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: wikimedia-foundation

Published: 2026-04-07T19:17:51.638Z

Updated: 2026-04-07T20:42:43.371Z

Reserved: 2026-04-07T18:21:12.573Z

Link: CVE-2026-39838

Vulnrichment

Updated: 2026-04-07T20:40:11.397Z

NVD

Status : Received

Published: 2026-04-07T20:16:33.477

Modified: 2026-04-07T20:16:33.477

Link: CVE-2026-39838

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-79

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