CVE-2026-55691
EmbedVideo Extension : Stored XSS via unsanitized class passed to template
HIGH 8.6EPSS 0.5%
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 value directly to sprintf while constructing a figure element. A quote in the class value can terminate the class attribute and inject arbitrary HTML attributes or markup into the rendered page. A user able to edit a wiki page can store JavaScript that executes for visitors who render the affected content. This issue is fixed in version 4.1.0.
- Affected
- StarCitizenWiki · mediawiki-extensions-EmbedVideo
- CVSS v3.1 GITHUB
- 8.6 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L - EPSS
- 0.48% chance of exploitation in the next 30 days, 40th percentile
- Published
- 2026-09-15
- Updated
- 2026-09-16