A communication device may accept an input of user authentication information, cause an output unit to output specific information obtained by using a public key in a case where authentication using the inputted user authentication information is successful. In a case where the authentication using the inputted user authentication information fails, the specific information is not outputted. The communication device may receive an authentication request in which the public key is used from a first external device, send an authentication response to the first external device, receive first connection information from the first external device, and establish a first wireless connection between the communication device and a second external device by using the first connection information.