An information disclosure vulnerability exists in Ruijie NBR series routers (known to affect NBR2000G, NBR1300G, and NBR1000 models) via the /WEB_VMS/LEVEL15/ endpoint. By crafting a specific POST request with modified Cookie headers and specially formatted parameters, an unauthenticated attacker can retrieve administrative account credentials in plaintext. This flaw allows direct disclosure of sensitive user data due to improper authentication checks and insecure backend logic.