CVE-2026-55692: EmbedVideo Extension: Stored XSS via malformed src url with $wgEmbedVideoRequireConsent enabled

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-15 · updated 2026-09-30
Weakness: CWE-79

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 the default $wgEmbedVideoRequireConsent configuration enabled, includes/EmbedService/EmbedHtmlFormatter.php places JSON returned through includes/EmbedService/AbstractEmbedService.php into the data-mw-iframeconfig attribute without safely escaping single quotes. Attacker-controlled archiveorg identifiers and wistia or sharepoint URLs accepted by the affected service validators can cause getUrl() output to terminate the attribute and inject event-handler attributes into the generated figure element. A user able to edit a wiki page can store JavaScript that executes in the wiki origin when visitors render the page. This issue is fixed in version 4.1.0.

Affected products

StarCitizenWiki mediawiki-extensions-EmbedVideo: before 4.1.0

References

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