luci-app-upnp Stored XSS via UPnP Port Mapping Description

luci-app-upnp contains a stored cross-site scripting vulnerability that allows unauthenticated LAN clients to inject JavaScript via UPnP IGD AddPortMapping SOAP requests. Attackers can send malicious HTML in the NewPortMappingDescription field, which miniupnpd stores and luci-app-upnp renders without output encoding, executing the payload when administrators view the UPnP or Status pages.