librabbitmq: integer overflow in amqp_handle_input in amqp_connection.c leads to heap-based buffer overflow

An issue was discovered in amqphandleinput in amqpconnection.c in rabbitmq-c 0.9.0. There is an integer overflow that leads to heap memory corruption in the handling of CONNECTIONSTATEHEADER. A rogue server could return a malicious frame header that leads to a smaller targetsize value than needed...