CVE-2026-118253: Highcharts Dashboards parses fullscreen labels as HTML

The edit mode fullscreen labels are parsed as HTML when the corresponding control is rendered. An attacker who controls the Dashboards language options can supply markup carrying event handlers, which then execute in the origin of the page hosting the dashboard. Exploitation requires that untrusted data reach the Dashboards language configuration and that the affected control be rendered. Script running this way has the same access to page data, storage and session state as the hosting application.