Null Pointer Dereference vulnerability in TRENDnet TEW-755AP 1.11B03 TEW-755AP2KAC 1.11B03 TEW-821DAP2KAC 1.11B03 and TEW-825DAP 1.11B03 which could let a remote malicious user cause a denial of service by sending a POST request to apply_cgi via an action ping_test without a ping_ipaddr key.