There is a debug-interface vulnerability on some Tenda routers (FH1202/F1202/F1200: versions before 1.2.0.20). After connecting locally to a router in a wired or wireless manner, one can bypass intended access restrictions by sending shell commands directly and reading their results, or by entering shell commands that change this router's username and password.
There is a stack-based buffer overflow on some Tenda routers (FH1202/F1202/F1200: versions before 1.2.0.20). Crafted POST requests to an unspecified URL result in DoS, interrupting the HTTP service (used to login to the web UI of a router) for 1 to 2 seconds.