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...

EUVD-2026-78832

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...

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...

CVE-2026-55691

CVE-2026-55691 is a stored XSS in the EmbedVideo MediaWiki extension (by StarCitizenWiki), affecting versions prior to 4.1.0 . The root cause is in EmbedHtmlFormatter::toHtml, where a user-supplied class value is passed directly to sprintf without escaping when constructing a element. A single q...