Mediawiki EmbedVideo Extension has stored XSS via malformed src url with $wgEmbedVideoRequireConsent disabled (CVE-2026-57440) | HOL Guard CVE

High · CVSS 7.5CVE-2026-57440

Mediawiki EmbedVideo Extension has stored XSS via malformed src url with $wgEmbedVideoRequireConsent disabled

Answer in brief

CVE-2026-57440 records a High severity (CVSS 7.5) vulnerability in Mediawiki EmbedVideo Extension has stored XSS via malformed src url with $wgEmbedVideoRequireConsent disabled. The current sources do not mark it as known exploited. The current feed maps StarCitizenWiki/mediawiki-extensions-EmbedVideo (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 24, 2026Updated Sep 24, 2026Source checked Sep 25, 2026First seen by HOL Sep 25, 2026Material review Sep 24, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 7.5
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps StarCitizenWiki/mediawiki-extensions-EmbedVideo (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
StarCitizenWiki/mediawiki-extensions-EmbedVideogeneric	<4.1.0	4.1.0

Recommended response

Check inventory. Check lockfiles and deployed manifests for StarCitizenWiki/mediawiki-extensions-EmbedVideo.
Review the reported fix. Update StarCitizenWiki/mediawiki-extensions-EmbedVideo to 4.1.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 24, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 24, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 25, 2026

Sources and claim methodology

Upstream source description

The EmbedVideo Extension is a MediaWiki extension which adds a parser function called #ev and various parser tags for embedding video clips from various video sharing services. Prior to 4.1.0, with $wgEmbedVideoRequireConsent disabled (not the default), the urls for videos are passed into an iframe src attribute without sanitization. When given a malformed url or id, the src attribute can be escaped via double quotes, allowing for html/javascript injection. Version 4.1.0 contains a patch.

Quoted source text, attributed separately from HOL analysis.