Tries to get Telnet login credentials by guessing usernames and passwords. SYNTAX: userdb: The filename of an alternate username database. unpwdb.passlimit: The maximum number of passwords 'passwords' will return (default unlimited). passdb: The filename of an alternate password database. unpwdb.userlimit: The maximum number of usernames 'usernames' will return (default unlimited). unpwdb.timelimit: The maximum amount of time that any iterator will run before stopping. The value is in seconds by default and you can follow it with 'ms', 's', 'm', or 'h' for milliseconds, seconds, minutes, or hours. For example, 'unpwdb.timelimit=30m' or 'unpwdb.timelimit=.5h' for 30 minutes. The default depends on the timing template level (see the module description). Use the value '0' to disable the time limit.