Netcore NR256CN through 1.5.140116 Boa Web Server NULL Pointer Dereference DoS

Netcore NR256CN through 1.5.140116 contains a NULL pointer dereference vulnerability in the Boa web server's user_auth() function that allows unauthenticated attackers to crash the server via a malformed Authorization header. Attackers can send a Basic Authorization value lacking a colon, such as one decoding to a single character, to protected routes like /router/get_user_type.cgi to kill the main Boa process and deny management interface access.