A memory system includes a nonvolatile memory device; and a controller configured to control the nonvolatile memory device, wherein the controller is configured to: receive a system information request including a command and an argument from a host device; determine suitability of the system information request based on a fixed key included in the argument in response to the command; encrypt system information based the argument when the system information request is suitable; and transmit the encrypted system information to the host device.