SuperPlane before 0.27.0 contains a broken object-level authorization vulnerability in the CanvasService gRPC handlers that allows authenticated users with viewer-level access to one organization to access resources belonging to other organizations by supplying arbitrary canvas or queue UUIDs without organization scoping. Attackers can read cross-tenant execution history and event payloads containing sensitive secrets, write queue items and canvas events into victim organizations, delete arbitrary canvases, and disrupt automation workflows across tenant boundaries.