CVE-2026-55691
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.
Scoring
- Severity
- HIGH
- CVSS base score
- 8.6
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L
- EPSS probability
- 0.29%
- CWE
- CWE-79
- Published
- 2026-09-15
- Last modified
- 2026-09-16
Affected products
- StarCitizenWiki mediawiki-extensions-EmbedVideo
Weakness type
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