Abstract: A device for detecting a command and control channel includes: a session log collector for collecting log information of sessions generated between at least one communication device of the first network and at least one communication device of the second network; an analyzer for generating test data for respective sessions based on the log information, and calculating a test data distribution based on test data of the sessions; and a determiner for extracting a test data value corresponding to an abnormal distribution from the test data distribution based on an abnormal distribution determination standard, and estimating sessions relating to the extracted test data value as a command and control channel.