EmbedVideo Extension vulnerabilities

The EmbedVideo extension for MediaWiki prior to 4.1.0, with the default $wgEmbedVideoRequireConsent configuration, places JSON into the data-mw-iframeconfig attribute without safely escaping single quotes. Attacker-controlled archiveorg identifiers and wistia or sharepoint URLs can terminate the attribute and inject event-handler attributes into the generated figure element.

The EmbedVideo extension for MediaWiki prior to 4.1.0 passes the user-supplied class value directly to sprintf when 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.

The EmbedVideo extension for MediaWiki prior to 4.1.0 interpolates an attacker-controlled unknown service name into exception text, then returns that text as HTML without neutralization. Both the #ev parser function and the evl parser form can reach this error path.