win2ban Installation/Usage

Installation

Supported platforms: Vista/2008(R2)/7/8/2012(R2)/2016

win2ban comes as a zip archive containing a Nullsoft Installer package. Unzip the downloaded file and run  the installer :

  1. Click Next at Welcome-page
  2. View license agreement.
  3. Specify an installation location.
  4. Select components to install. You can choose not to install Winlogbeat if there is no need for making eventlog entries available for processing via Fail2ban in your case.
  5. Installation starts and installs Fail2ban and optional Winlogbeat as services (win2ban_fail2ban and win2ban_winlogbeat) 

Usage

Fail2ban configuration files are located at etc/fail2ban. Win2ban is ready-to-protect against RDP/Network login or Copssh SSH attacks out of the box. Otherwise, you need to develop/implement your jails according to your needs. The file jail.local is configured with a proper set of default parameters for Windows usage. The file windows-firewall.local in the action.d directory contains ban/unban commands for the Windows firewall. It is also possible to configure the server using commands sent to it by fail2ban-client. A shell environment can be initiated by running win2ban-shell.cmd located at the root of the installation directory.  

Fail2ban log example (var/log/fail2ban.log):

2021-05-09 20:02:21,048 fail2ban.server         : INFO    --------------------------------------------------
2021-05-09 20:02:21,048 fail2ban.server         : INFO    Starting Fail2ban v0.10.4
2021-05-09 20:02:21,155 fail2ban.database       : INFO    Connected to fail2ban persistent database '/var/lib/fail2ban/fail2ban.sqlite3'
2021-05-09 20:02:21,168 fail2ban.database       : WARNING New database created. Version '2'
2021-05-09 20:02:21,170 fail2ban.jail           : INFO    Creating new jail 'win2ban-network-logon'
2021-05-09 20:02:21,171 fail2ban.jail           : INFO    Jail 'win2ban-network-logon' uses poller {}
2021-05-09 20:02:21,171 fail2ban.jail           : INFO    Initiated 'polling' backend
2021-05-09 20:02:21,177 fail2ban.filter         : INFO    Added logfile: '/winlogbeat/logs/eventlog' (pos = 0, hash = 5acf97560c9b8014a621577ff3b4bda5)
2021-05-09 20:02:21,177 fail2ban.filter         : INFO      maxRetry: 2
2021-05-09 20:02:21,178 fail2ban.filter         : INFO      encoding: UTF-8
2021-05-09 20:02:21,179 fail2ban.filter         : INFO      findtime: 600
2021-05-09 20:02:21,179 fail2ban.actions        : INFO      banTime: 600
2021-05-09 20:02:21,180 fail2ban.jail           : INFO    Creating new jail 'copssh'
2021-05-09 20:02:21,181 fail2ban.jail           : INFO    Jail 'copssh' uses poller {}
2021-05-09 20:02:21,181 fail2ban.jail           : INFO    Initiated 'polling' backend
2021-05-09 20:02:21,182 fail2ban.filter         : INFO      maxLines: 1
2021-05-09 20:02:21,201 fail2ban.server         : INFO    Jail copssh is not a JournalFilter instance
2021-05-09 20:02:21,203 fail2ban.filter         : INFO    Added logfile: '/winlogbeat/logs/eventlog' (pos = 0, hash = 5acf97560c9b8014a621577ff3b4bda5)
2021-05-09 20:02:21,203 fail2ban.filter         : INFO      maxRetry: 2
2021-05-09 20:02:21,203 fail2ban.filter         : INFO      encoding: UTF-8
2021-05-09 20:02:21,204 fail2ban.filter         : INFO      findtime: 600
2021-05-09 20:02:21,204 fail2ban.actions        : INFO      banTime: 600
2021-05-09 20:02:21,211 fail2ban.jail           : INFO    Jail 'win2ban-network-logon' started
2021-05-09 20:02:21,213 fail2ban.jail           : INFO    Jail 'copssh' started
2021-05-09 20:04:52,886 fail2ban.filter         : INFO     Found 192.168.100.22 - 2021-05-09 20:04:49
2021-05-09 20:05:03,081 fail2ban.filter         : INFO     Found 192.168.100.22 - 2021-05-09 20:05:00
2021-05-09 20:05:03,299 fail2ban.actions        : NOTICE   Ban 192.168.100.22

 

If you have selected to install winlogbeat, it can be configured via winlogbeat/win2ban.yml. By default it is configured to output related event log entries last 72 hours from application, system and security eventlogs, to the logfile winlogbeat\logs\eventlog with the following format:

string: '%{} %{} %{}'

 example output:

2018-03-24T10:22:09.000Z 1704 Security policy in the Group policy objects has been applied successfully.

 

 Some good references for fail2ban/winlogbeat usage: 

Official Fail2ban Website

Man pages: fail2ban    jail.conf    fail2ban-client    fail2ban-regex    fail2ban-server

Linode.com - Use Fail2ban to Secure Your Server

 Winlogbeat reference