Please Help! How to STOP them...

[VeeJay]

What should be ENABLED and what should be DISABLED?

#       $OpenBSD: sshd_config,v 1.74 2006/07/19 13:07:10 dtucker Exp $
#       $FreeBSD: src/crypto/openssh/sshd_config,v 1.42.2.4 2006/11/11
00:51:28 des Exp $

# This is the sshd server system-wide configuration file.  See
# sshd_config(5) for more information.

# This sshd was compiled with PATH=/usr/bin:/bin:/usr/sbin:/sbin

# The strategy used for options in the default sshd_config shipped with
# OpenSSH is to specify options with their default value where
# possible, but leave them commented.  Uncommented options change a
# default value.

# Note that some of FreeBSD's defaults differ from OpenBSD's, and
# FreeBSD has a few additional options.

#VersionAddendum FreeBSD-20061110

#Port 22
#Protocol 2
#AddressFamily any
#ListenAddress 0.0.0.0
#ListenAddress ::

# HostKey for protocol version 1
#HostKey /etc/ssh/ssh_host_key
# HostKeys for protocol version 2
#HostKey /etc/ssh/ssh_host_dsa_key

# Lifetime and size of ephemeral version 1 server key
#KeyRegenerationInterval 1h
#ServerKeyBits 768

# Logging
# obsoletes QuietMode and FascistLogging
#SyslogFacility AUTH
#LogLevel INFO

# Authentication:

#LoginGraceTime 2m
#PermitRootLogin no
#StrictModes yes
#MaxAuthTries 6

#RSAAuthentication yes
#PubkeyAuthentication yes
#AuthorizedKeysFile     .ssh/authorized_keys

# For this to work you will also need host keys in /etc/ssh/ssh_known_hosts
#RhostsRSAAuthentication no
# similar for protocol version 2
#HostbasedAuthentication no
# Change to yes if you don't trust ~/.ssh/known_hosts for
# RhostsRSAAuthentication and HostbasedAuthentication
#IgnoreUserKnownHosts no
# Don't read the user's ~/.rhosts and ~/.shosts files
#IgnoreRhosts yes

# Change to yes to enable built-in password authentication.
#PasswordAuthentication no
#PermitEmptyPasswords no

# Change to no to disable PAM authentication
#ChallengeResponseAuthentication yes

# Kerberos options
#KerberosAuthentication no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes
#KerberosGetAFSToken no

# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes

# Set this to 'no' to disable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication.  Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
#UsePAM yes

#AllowTcpForwarding yes
#GatewayPorts no
#X11Forwarding yes
#X11DisplayOffset 10
#X11UseLocalhost yes
#PrintMotd yes
#PrintLastLog yes
#TCPKeepAlive yes
#UseLogin no
#UsePrivilegeSeparation yes
#PermitUserEnvironment no
#Compression delayed
#ClientAliveInterval 0
#ClientAliveCountMax 3
#UseDNS yes
#PidFile /var/run/sshd.pid
#MaxStartups 10
#PermitTunnel no

# no default banner path
#Banner /some/path

# override default of no subsystems
Subsystem       sftp    /usr/libexec/sftp-server

# Example of overriding settings on a per-user basis
#Match User anoncvs
#       X11Forwarding no
#       AllowTcpForwarding no
#       ForceCommand cvs server

What steps need to follow?




On 1/12/07, VeeJay <maanjee at gmail.com> wrote:
>
> Thanks Reko....
>
> Just couple of more questions...
>
>
> On 1/12/07, Reko Turja <reko.turja at liukuma.net> wrote:
> >
> > From: "VeeJay" <maanjee at gmail.com>
> > To: < maanjee at gmail.com>; "FreeBSD-Questions"
> > <freebsd-questions at freebsd.org>
> > Sent: Friday, January 12, 2007 11:43 PM
> > Subject: Please Help! How to STOP them...
> >
> >
> > >I am reading many hundred lines similar to below mentioned?
> > >
> > > Could you please advise me what to do and how can I make my box more
> > > secure?
> > >
> > > Jan  9 17:54:42 localhost sshd[5130]: reverse mapping checking
> > > getaddrinfo
> > > for bbs-83-179.189.218.on-nets.com [218.189.179.83] failed -
> > > POSSIBLE
> > > BREAK-IN ATTEMPT!
> > > Jan  9 17:54:42 localhost sshd[5130]: Invalid user sysadmin from
> > > 218.189.179.83
> >
> > It's basically just script kiddies trying to get in using some ready
> > made user/password pairs.
> >
> > Lots of info covering this has been posted in these newsgroups
> > previously, but some things you might consider
> >
> > Moving your sshd port somewhere else than 22 - the prepackaged
> > "cracking" programs don't scan ports, just blindly try out the default
> > port - with determined/skilled attacker it's different matter entirely
> > though.
>
>
> How to change the port from 22 to something other and in what range should
> I choose a number?
>
>
> Use some kind of portblocker (lots in ports tree) which closes the
> > port after predetermined number of attempts - or as an alternative,
> > use PF to close the port for IP's in question after predetermined
> > number of connection attempts in given time.
>
>
> Can you suggest such port which I should install to block these attempts?
>
> Use key based authentication and stop using passwords altogether.
>
>
> What do you mean here?
>
> Remember to keep ssh1 disabled as well as direct root access into ssh
> > from the ssh config file.
>
>
> How to disable SSH1 and How to stop direct root access into ssh, where to
> change?
>
> -Reko
> >
> >
>
>
> --
> Thanks!
>
> BR / vj




-- 
Thanks!

BR / vj