fail2ban-ss-kill-connection

Usage

Copy:

cp ./ss-kill-custom.conf /etc/fail2ban/action.d/
cp ./ss-kill-subnet-custom.conf /etc/fail2ban/action.d/

Adjust jail.local file
/etc/fail2ban/jail.local

[ftp]
(...)
action = (your normal action)
         ss-kill-custom[port="21,50000:51000"]
         
[ftp-subnet]
(...)
action = (your normal action)
         ss-kill-subnet-custom[port="21,50000:51000",mask4="24",mask6="64"]