This article outlines the process of configuring Fail2Ban to secure a Horde Webmail, running on a Plesk server, against brute force attacks.
Prerequisite: This article expects that you have already completed the installation of Fail2Ban as outlined here.
Once you have completed the installation of Fail2Ban –
1. Copy the Courier IMAP filter to a new filter for Horde:
# cp /etc/fail2ban/filter.d/courierlogin.conf /etc/fail2ban/filter.d/hordelogin.conf
2. Edit the contents of /etc/fail2ban/filter.d/hordelogin.conf
# nano -w /etc/fail2ban/filter.d/hordelogin.conf
The file should read:
failregex = FAILED LOGIN for *.* \[< HOST >\] .*$
3. Edit the Fail2Ban jail file:
# nano -w /etc/fail2ban/jail.conf
4. At the end of the file add: Continue reading “How to protect Horde Webmail (Plesk) against brute force attacks”