Linux Tutorial and something else…..

a) Create configuration file
vim /etc/fail2ban/filter.d/wordpress.conf

# Fail2Ban filter for WordPress hard failures
#

[INCLUDES]

before = common.conf

[Definition]

_daemon = (?:wordpress|wp)

failregex = .*<HOST> – – .* “POST \/wp-login\.php HTTP\/1\.1” 200 (5127|5128|5129|5130) .*
.*<HOST> – – .* “POST \/xmlrpc\.php HTTP\/1\.1” 200 (5127|5128|5129|5130) .*
.*<HOST> – – .* “POST \/blog\/wp-login\.php HTTP\/1\.1” 200 (5127|5128|5129|5130) .*
.*<HOST> – – .* “POST \/web\/wp-login\.php HTTP\/1\.1” 200 (5127|5128|5129|5130) .*
ignoreregex =

b) set jail.conf

[wordpress]

enabled = true
filter = wordpress
action = iptables-multiport[name=wordpress, port=”http,https”, dest=postmaster@saic.it, sender=postmaster@saic.it]
logpath = /var/log/httpd/access_log
maxretry = 5
port = http,https
findtime = 300
bantime = 10800

restart failban

 

 

vi /etc/fail2ban/filter.d/ispconfig.conf
The first thing we need to do is create a filter for ISPconfig in the /etc/fail2ban/filter.d/ directory.

vi /etc/fail2ban/filter.d/ispconfig.conf
Add the following definition so the filter knows what to look for in the /var/log/ispconfig/auth.log for ISPConfig 3.

# Fail2Ban filter for ISPConfig hard failures
#

[INCLUDES]

before = common.conf

[Definition]

_daemon = (?:ispconfig)

failregex = Failed login for user .* from <HOST>
ignoreregex =

vim /etc/fail2ban/jail.conf

add this line

[ispconfig]
enabled = true
port = 8080
filter = ispconfig
action = iptables-multiport[name=wordpress, port=”http,https”, dest=postmaster@saic.it, sender=postmaster@saic.it]
logpath = /var/log/ispconfig/auth.log
maxretry = 3
findtime = 300
bantime = 10800
You can/should test the new configuration by running the following command.

fail2ban-regex /var/log/ispconfig/auth.log /etc/fail2ban/filter.d/ispconfig.conf

THEN Restart fail2ban to load your new jail for ISPConfig 3 failed login attempts.

service fail2ban restart

usefull

https://www.digitalocean.com/community/tutorials/how-fail2ban-works-to-protect-services-on-a-linux-server

Today I found an error in the regular expression of failban filter :

/etc/fail2ban/filter.d/postfix-sasl.conf

with this useful site https://regex101.com/ gave me an error so I changed the expression from

failregex = ^%(__prefix_line)swarning: [-._\w]+\[<HOST>\]: SASL ((?i)LOGIN|PLAIN|(?:CRAM|DIGEST)-MD5) authentication failed(: [ A-Za-z0-9+/:]*={0,2})?\s*     

failregex = ^%(__prefix_line)swarning: [-._\w]+\[<HOST>\]: SASL ((?i)LOGIN|PLAIN|(?:CRAM|DIGEST)-MD5) authentication failed(: [ A-Za-z0-9+\/:]*={0,2})?\s*     

failban conf file : jail.conf

[postfix-sasl]

enabled = true
filter = postfix-sasl
action = iptables[name=postfix-sasl, port=”smtp,465,submission,imap3,imaps,pop3,pop3s”, protocol=tcp]
sendmail-whois[name=postfix-sasl, dest=postmaster@saic.it, sender=postmaster@saic.it]
#port = smtp,465,submission,imap3,imaps,pop3,pop3s
# You might consider monitoring /var/log/mail.warn instead if you are
# running postfix since it would provide the same log lines at the
# “warn” level but overall at the smaller filesize.
logpath = %(postfix_log)s
backend = %(postfix_backend)s
maxretry = 3
bantime = 10800

here /etc/fail2ban/paths-fedora.conf the configuration of the variable postfix_log and postfix_backend

http://www.fail2ban.org/wiki/index.php/Fail2ban:Community_Portal