Insecure Access Control on TP-Link Tapo D235 and C260

On TP-Link Tapo C260 v1 and D235 v1, a guest‑level authenticated user can bypass intended access restrictions by sending crafted requests to a synchronization endpoint. This allows modification of protected device settings despite limited privileges. An attacker may change sensitive configuration parameters without authorization, resulting in unauthorized device state manipulation but not full code execution.