Neil Aggarwal
2009-Jul-09 14:56 UTC
[CentOS] Looking for recommendations for blocking hacking attempts
Hello: I have been looking into projects that will automatically restrict hacking attempts on my servers running CentOS 5. I think the two top contenders are: DenyHosts - http://denyhosts.sourceforge.net Fail2ban - http://www.fail2ban.org>From what I see, DenyHosts only blocks based on failedSSH attempts whereas Fail2ban blocks failed attempts for other access as well. The main benefit I see from DenyHosts is their synchronization service where my servers can proactively block hosts recognized by other users of their service. Does anyone have experience with these tools and have recommendations? Thanks, Neil -- Neil Aggarwal, (281)846-8957, www.JAMMConsulting.com Will your e-commerce site go offline if you have a DB server failure, fiber cut, flood, fire, or other disaster? If so, ask me about our geographically redudant database system.
Ron Loftin
2009-Jul-09 15:16 UTC
[CentOS] Looking for recommendations for blocking hacking attempts
On Thu, 2009-07-09 at 09:56 -0500, Neil Aggarwal wrote:> Hello: > > I have been looking into projects that will automatically > restrict hacking attempts on my servers running CentOS 5. > > I think the two top contenders are: > DenyHosts - http://denyhosts.sourceforge.net > Fail2ban - http://www.fail2ban.org > > >From what I see, DenyHosts only blocks based on failed > SSH attempts whereas Fail2ban blocks failed attempts > for other access as well.That is incorrect. Denyhosts has a config option named "BLOCK_SERVICE" which can be set to "ALL". Check out the description included in the sample config file. I have been using Denyhosts for at least 3 years now, and been satisfied enough with it that I have not gone looking for alternatives, so I can't rationally compare it with Fail2ban. I have seen numerous reports on the Web of people being happy with Fail2ban, so I guess it comes down to which one you are comfortable with. The only other observation I have is that most of my machines have very few services exposed to the Internet. Most services on my Internet-facing boxes are either disabled or limited by firewall rules, so the Denyhosts/Fail2ban layer gets less work. I suggest that you critically evaluate the services you choose to make available to the 'Net from a similar viewpoint. Just my $0.02 (US) worth. ;>> > The main benefit I see from DenyHosts is their synchronization > service where my servers can proactively block hosts recognized > by other users of their service. > > Does anyone have experience with these tools and have > recommendations? > > Thanks, > Neil > > -- > Neil Aggarwal, (281)846-8957, www.JAMMConsulting.com > Will your e-commerce site go offline if you have > a DB server failure, fiber cut, flood, fire, or other disaster? > If so, ask me about our geographically redudant database system. > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos-- Ron Loftin reloftin at twcny.rr.com "God, root, what is difference ?" Piter from UserFriendly
mark.hanna at rmgconnect.com
2009-Jul-09 17:18 UTC
[CentOS] Looking for recommendations for blocking hacking attempts
If you are talking about restricting "hacking" attempts across
multiple
services (like ssh, smtp and http) then you are beginning to move into the
realm of an IDS solution (like Snort)
Currently I use denyhosts plus iptables blacklist for ssh on the servers
side (plus multiple layers of firewall devices in front of the servers)...
I could go with either denyhosts OR iptables, but I believe multiple
methods is prudent in case one method fails
This is what my (editted) iptables listing looks like for the blacklisting
Chain INPUT (policy DROP)
target prot opt source destination
SSH tcp -- anywhere anywhere state NEW tcp
dpt:ssh
Chain BLACKLIST (3 references)
target prot opt source destination
all -- anywhere anywhere recent: SET
name: BLACKLIST side: source
DROP all -- anywhere anywhere
Chain SSH (1 references)
target prot opt source destination
DROP all -- anywhere anywhere recent:
UPDATE seconds: 3600 hit_count: 1 name: BLACKLIST side: source
all -- anywhere anywhere recent: SET
name: COUNT1 side: source
all -- anywhere anywhere recent: SET
name: COUNT2 side: source
all -- anywhere anywhere recent: SET
name: COUNT3 side: source
BLACKLIST all -- anywhere anywhere recent:
UPDATE seconds: 60 hit_count: 5 name: COUNT1 side: source
BLACKLIST all -- anywhere anywhere recent:
UPDATE seconds: 300 hit_count: 10 name: COUNT2 side: source
BLACKLIST all -- anywhere anywhere recent:
UPDATE seconds: 1800 hit_count: 20 name: COUNT3 side: source
ACCEPT all -- anywhere anywhere
So if someone connects via ssh more than 5 times in one minute, 10 times
in 5 minutes or 20 times in 30 minutes, they are blacklisted for an
hour...
"Neil Aggarwal" <neil at JAMMConsulting.com>
Sent by: centos-bounces at centos.org
07/09/2009 09:57 AM
Please respond to
CentOS mailing list <centos at centos.org>
To
"''CentOS mailing list''" <centos at centos.org>
cc
Subject
[CentOS] Looking for recommendations for blocking hacking attempts
Hello:
I have been looking into projects that will automatically
restrict hacking attempts on my servers running CentOS 5.
I think the two top contenders are:
DenyHosts - http://denyhosts.sourceforge.net
Fail2ban - http://www.fail2ban.org
>From what I see, DenyHosts only blocks based on failed
SSH attempts whereas Fail2ban blocks failed attempts
for other access as well.
The main benefit I see from DenyHosts is their synchronization
service where my servers can proactively block hosts recognized
by other users of their service.
Does anyone have experience with these tools and have
recommendations?
Thanks,
Neil
--
Neil Aggarwal, (281)846-8957, www.JAMMConsulting.com
Will your e-commerce site go offline if you have
a DB server failure, fiber cut, flood, fire, or other disaster?
If so, ask me about our geographically redudant database system.
_______________________________________________
CentOS mailing list
CentOS at centos.org
http://lists.centos.org/mailman/listinfo/centos
</PRE><p><span
style="font-size:9.5pt;line-height:115%;font-family: Arial">This
transmission is intended solely for the person or organization to whom it is
addressed and it may contain privileged and confidential information. If you
are not the intended recipient you should not copy, distribute or take any
action in reliance on it. If you believe you received this transmission in
error, please notify the sender.</span></p>
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
http://lists.centos.org/pipermail/centos/attachments/20090709/44a2baa4/attachment.html
mark.hanna at rmgconnect.com
2009-Jul-09 17:18 UTC
[CentOS] Looking for recommendations for blocking hacking attempts
If you are talking about restricting "hacking" attempts across
multiple
services (like ssh, smtp and http) then you are beginning to move into the
realm of an IDS solution (like Snort)
Currently I use denyhosts plus iptables blacklist for ssh on the servers
side (plus multiple layers of firewall devices in front of the servers)...
I could go with either denyhosts OR iptables, but I believe multiple
methods is prudent in case one method fails
This is what my (editted) iptables listing looks like for the blacklisting
Chain INPUT (policy DROP)
target prot opt source destination
SSH tcp -- anywhere anywhere state NEW tcp
dpt:ssh
Chain BLACKLIST (3 references)
target prot opt source destination
all -- anywhere anywhere recent: SET
name: BLACKLIST side: source
DROP all -- anywhere anywhere
Chain SSH (1 references)
target prot opt source destination
DROP all -- anywhere anywhere recent:
UPDATE seconds: 3600 hit_count: 1 name: BLACKLIST side: source
all -- anywhere anywhere recent: SET
name: COUNT1 side: source
all -- anywhere anywhere recent: SET
name: COUNT2 side: source
all -- anywhere anywhere recent: SET
name: COUNT3 side: source
BLACKLIST all -- anywhere anywhere recent:
UPDATE seconds: 60 hit_count: 5 name: COUNT1 side: source
BLACKLIST all -- anywhere anywhere recent:
UPDATE seconds: 300 hit_count: 10 name: COUNT2 side: source
BLACKLIST all -- anywhere anywhere recent:
UPDATE seconds: 1800 hit_count: 20 name: COUNT3 side: source
ACCEPT all -- anywhere anywhere
So if someone connects via ssh more than 5 times in one minute, 10 times
in 5 minutes or 20 times in 30 minutes, they are blacklisted for an
hour...
"Neil Aggarwal" <neil at JAMMConsulting.com>
Sent by: centos-bounces at centos.org
07/09/2009 09:57 AM
Please respond to
CentOS mailing list <centos at centos.org>
To
"'CentOS mailing list'" <centos at centos.org>
cc
Subject
[CentOS] Looking for recommendations for blocking hacking attempts
Hello:
I have been looking into projects that will automatically
restrict hacking attempts on my servers running CentOS 5.
I think the two top contenders are:
DenyHosts - http://denyhosts.sourceforge.net
Fail2ban - http://www.fail2ban.org
>From what I see, DenyHosts only blocks based on failed
SSH attempts whereas Fail2ban blocks failed attempts
for other access as well.
The main benefit I see from DenyHosts is their synchronization
service where my servers can proactively block hosts recognized
by other users of their service.
Does anyone have experience with these tools and have
recommendations?
Thanks,
Neil
--
Neil Aggarwal, (281)846-8957, www.JAMMConsulting.com
Will your e-commerce site go offline if you have
a DB server failure, fiber cut, flood, fire, or other disaster?
If so, ask me about our geographically redudant database system.
_______________________________________________
CentOS mailing list
CentOS at centos.org
http://lists.centos.org/mailman/listinfo/centos
</PRE><p><span
style="font-size:9.5pt;line-height:115%;font-family: Arial">This
transmission is intended solely for the person or organization to whom it is
addressed and it may contain privileged and confidential information. If you
are not the intended recipient you should not copy, distribute or take any
action in reliance on it. If you believe you received this transmission in
error, please notify the sender.</span></p>
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://lists.centos.org/pipermail/centos/attachments/20090709/44a2baa4/attachment-0003.html>