Log estranho no auth.log

[xcompbrasil]

As seguintes mensagens estao aparecendo no arquivo auth.log

Jun 19 06:30:03 wserv CRON[17448]: (pam_unix) session closed for user root
Jun 19 06:39:01 wserv CRON[17490]: (pam_unix) session opened for user root by (uid=0)
Jun 19 06:39:01 wserv CRON[17492]: (pam_unix) session opened for user root by (uid=0)
Jun 19 06:39:01 wserv CRON[17492]: (pam_unix) session closed for user root
Jun 19 06:39:01 wserv CRON[17490]: (pam_unix) session closed for user root
Jun 19 06:51:14 wserv sshd[17567]: Did not receive identification string from 200.171.128.188
Jun 19 07:09:02 wserv CRON[17641]: (pam_unix) session opened for user root by (uid=0)
Jun 19 07:09:02 wserv CRON[17643]: (pam_unix) session opened for user root by (uid=0)
Jun 19 07:09:02 wserv CRON[17641]: (pam_unix) session closed for user root
Jun 19 07:09:02 wserv CRON[17643]: (pam_unix) session closed for user root
Jun 19 07:15:01 wserv CRON[17690]: (pam_unix) session opened for user root by (uid=0)
Jun 19 07:15:05 wserv CRON[17690]: (pam_unix) session closed for user root
Jun 19 07:17:01 wserv CRON[17939]: (pam_unix) session opened for user root by (uid=0)
Jun 19 07:17:02 wserv CRON[17939]: (pam_unix) session closed for user root
Jun 19 07:30:01 wserv CRON[18113]: (pam_unix) session opened for user root by (uid=0)
Jun 19 07:30:01 wserv CRON[18114]: (pam_unix) session opened for user root by (uid=0)
Jun 19 07:30:04 wserv CRON[18113]: (pam_unix) session closed for user root
Jun 19 07:30:04 wserv CRON[18114]: (pam_unix) session closed for user root
Jun 19 07:39:02 wserv CRON[18346]: (pam_unix) session opened for user root by (uid=0)
Jun 19 07:39:02 wserv CRON[18347]: (pam_unix) session opened for user root by (uid=0)
Jun 19 07:39:02 wserv CRON[18346]: (pam_unix) session closed for user root
Jun 19 07:39:02 wserv CRON[18347]: (pam_unix) session closed for user root

Nao tem nada sendo executado no crontab nestes horarios.

Alguem sabe o que pode causar estas mensagens ?

[Duca]

Dá uma olhada nesse link:

http://www.linuxforums.org/forum/lin...hine-risk.html

Ab, Duca.