CVE-2026-57856 Cockpit CMS Path Traversal via Bucket Name in Bucket File Storage API

Cockpit CMS contains a path traversal vulnerability in the Bucket file storage API /system/buckets/api. The api method in modules/System/Controller/Buckets.php sanitizes the bucket name with pregreplace'/^a-zA-Z0-9-\./','', $bucket, which permits '..' and '../' sequences. The sanitized value is...