CVE-2026-55691 EmbedVideo Extension : Stored XSS via unsanitized class passed to template

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, EmbedHtmlFormatter::toHtml in includes/EmbedService/EmbedHtmlFormatter.php passes the user-supplied class...