topic Re: non system users access w/ ftp in Operating System - HP-UX

non system users access w/ ftp

johnson — Sun, 03 Sep 2000 01:58:50 GMT

HI:

I noticed several entries in the log:
/var/adm/syslog/syslog.log of non system
users trying to ftp into our HP UX (10.20 OS).

For example here is a typical entry:
Aug 30 04:09:50 sysname l ftpd[22956]: connection from a027068.ap.plala.or.jp at Wed Aug 30 04:09:50 2000

Most entries have European IP's.

Two questions:
1. Is this normal?
2. How can I make sure they did not succeed in getting into our system?

Re: non system users access w/ ftp

Vincente Fernandes — Sun, 03 Sep 2000 06:54:07 GMT

There are many ways to resolve your problem.
Looks like the network is accessible from outside where your server is physically located. If that is the case anyone can ftp to your server. One way to find out if the ftp connection succed. Check syslog.log if following line are present whenever someone tries to ftp.
Log for successful ftp:
Sep 03 03:31:44 sysname ftpd[7893]: connection from user_sys_name at Wed Sep 03 03:31:44 2000
Sep 03 03:31:44 sysname ftpd[7893]: FTP LOGIN FROM user_sys_name, xyz Sep 03 03:31:44 sysname ftpd[7893]: PORT
Sep 03 03:32:17 sysname ftpd[7893]: PORT
Sep 03 03:34:24 sysname ftpd[7893]: User xyz logged out

Also make sure that the network where is server is accessible only by valid users.

The below can be done only when you don't require ftp services on your server.
Comment below line from "/etc/inted.conf" if you want to disable ftp services on your server and restart inetd daemon from command line by "/usr/sbin/inetd -c".
ftp stream tcp nowait root /usr/lbin/ftpd ftpd -l
OR
comment the below lines from "/etc/services"
ftp-data 20/tcp # File Transfer Protocol (Data)
ftp 21/tcp # File Transfer Protocol (Control)

Re: non system users access w/ ftp

melvyn burnard — Sun, 03 Sep 2000 12:23:42 GMT

you may want to configure your inetd.sec file to deny access from any node outside of your network address
see man inetd.sec

Re: non system users access w/ ftp

James R. Ferguson — Sun, 03 Sep 2000 13:03:48 GMT

Wayn:

A couple of comments.

As already suggested, make sure that the ftpd deamon is run with logging when itetd starts. The -l option logs general session information. Adding the -v option wiil include files retrieved and stored to the syslog information. See: ftpd (1M).

For more information on the configuration of the /var/adm/inetd.sec security file, see inetd (4).

Ftpd can also be made to reject remote logins to local user accounts by configuring entries in /etc/ftpusers. See ftpusers (4).
You might find this gives you additional protection and/or peace-of-mind.

Lastly, there's no simplier approach than frequently changing passwords unless the FTP is anonymous.

..JRF...