Yeah from an extremely quick read of the code, I agree with atworkc. It's showing any IP address you have an established network connection to.

  void refreshConnections() {
    ssOutput =
        popen("ss -atun4 | grep ESTAB | awk '{print $6}' | cut -f1 -d\":\"", "r");

    if (ssOutput == NULL) {
      printf("Failed to run ss command\n");
      exit(1);
    }
  }

edit: ssOutput is a global variable which is read elsewhere.