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[root@estin201 ~]# tail /var/log/secure
Feb 17 19:05:41 estin201 sshd[1098]: reverse mapping checking getaddrinfo for 132.115.in-addr.arpa failed - POSSIBLE BREAK-IN ATTEMPT!
Feb 17 19:05:45 estin201 sshd[1098]: Accepted password for root from 115.132.84.249 port 32975 ssh2
Feb 17 19:05:45 estin201 sshd[1098]: pam_unix(sshd:session): session opened for user root by (uid=0)
Feb 17 19:07:33 estin201 sshd[1132]: reverse mapping checking getaddrinfo for 132.115.in-addr.arpa failed - POSSIBLE BREAK-IN ATTEMPT!
Feb 17 19:07:34 estin201 sshd[1132]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=115.132.84.249 user=root
Feb 17 19:07:36 estin201 sshd[1132]: Failed password for root from 115.132.84.249 port 35263 ssh2
[root@estin201 ~]#
Last edited by routers; 02-17-2009 at 05:05 AM.
Reason: confuse :)
Do you have the /etc/pam.d/vsftp file?
If you do, the second line I listed I created. Look at the manpage for pam_listfile. The item can be a hostname. So you can create a new file and use it as a host black list. (the /etc/hostname)
If you don't have an /etc/ftpusers file, your ftp service may not be configured. If it is used as a user blacklist, it should contain at least system users.
---
Look at "sudo /sbin/chkconfig vsftp". Does it say "on" or "xinetd"?
On Fedora and openSUSE, there is a /etc/pam.d/vsftp file that is used to control access and handle authentication for the vsftp service.
You may have it configured to be controlled by xinetd. If that is the case, then vsftp spawns a new service per request. The /etc/hosts.allow and /etc/hosts.deny controls should work.
Look for the /etc/xinet.d/vsftpd file. It tends to be used more for resource control. It defers access control to the vsftpd.conf file.
---
If your system uses pam, you can also add an entry in /etc/security/access.conf to control login access.
# Deny login access for anyone from 74.52.88.194
-:ALL:74.52.88.194
---
You can also add an iptables rule to drop the ip address in the firewall as well. This will protect all ports. Especially if you have a dedicated firewall which would drop the traffic before reaching your FTP server.
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