CVE-2026-125337: fallo de gravedad alta en wintercms winter

Winter CMS is a content management system built on the Laravel PHP framework. Prior to 1.2.14, the ImportExportController behavior applies userHasAccess() only to the import() and export() page actions, while Backend\Classes\Controller::execAjaxHandlers() dispatches onImport(), onImportLoadForm(), onImportLoadColumnSampleForm(), onExport(), and onExportLoadForm() before those gated actions run, and the separately reachable download() action also lacks the granular export check. An authenticated backend user with a valid session and coarse access through $requiredPermissions, but without the configured import[permissions] or export[permissions], can use the import handlers to write or overwrite records and can use onExport() followed by download() to retrieve the complete dataset exposed by the export model. Controllers without granular permission keys are unaffected because userHasAccess() is intentionally default-permissive. This issue is fixed in version 1.2.14.