To stop SSH/FTP attacks on your router, follow this advice.
This configuration allows only 10 FTP login incorrect answers per minute
in /ip firewall filter
add chain=input protocol=tcp dst-port=21 src-address-list=ftp_blacklist action=drop comment="drop ftp brute forcers" add chain=output action=accept protocol=tcp content="530 Login incorrect" dst-limit=1/1m,9,dst-address/1m add chain=output action=add-dst-to-address-list protocol=tcp content="530 Login incorrect" address-list=ftp_blacklist address-list-timeout=3h
This will prevent a SSH brute forcer to be banned for 10 days after repetitive attempts. Change the timeouts as necessary.
in /ip firewall filter
add chain=input protocol=tcp dst-port=22 src-address-list=ssh_blacklist action=drop comment="drop ssh brute forcers" disabled=no add chain=input protocol=tcp dst-port=22 connection-state=new src-address-list=ssh_stage3 action=add-src-to-address-list address-list=ssh_blacklist address-list-timeout=10d comment="" disabled=no add chain=input protocol=tcp dst-port=22 connection-state=new src-address-list=ssh_stage2 action=add-src-to-address-list address-list=ssh_stage3 address-list-timeout=1m comment="" disabled=no add chain=input protocol=tcp dst-port=22 connection-state=new src-address-list=ssh_stage1 action=add-src-to-address-list address-list=ssh_stage2 address-list-timeout=1m comment="" disabled=no add chain=input protocol=tcp dst-port=22 connection-state=new action=add-src-to-address-list address-list=ssh_stage1 address-list-timeout=1m comment="" disabled=no
If you want to block downstream access as well, you need to block the with the forward chain:
add chain=forward protocol=tcp dst-port=22 src-address-list=ssh_blacklist action=drop comment="drop ssh brute downstream" disabled=no
This will prevent a Telnet brute forcer to be banned forever after repetitive attempts. Change the timeouts as necessary.
in /ip firewall filter
add chain=input protocol=tcp dst-port=23 src-address-list=telnet_blacklist action=drop comment="drop telnet brute forcers" disabled=no add chain=input protocol=tcp dst-port=23 connection-state=new src-address-list=telnet_stage3 action=add-src-to-address-list address-list=telnet_blacklist address-list-timeout=1d comment="" disabled=no add chain=input protocol=tcp dst-port=23 connection-state=new src-address-list=telnet_stage2 action=add-src-to-address-list address-list=telnet_stage3 address-list-timeout=1m comment="" disabled=no add chain=input protocol=tcp dst-port=23 connection-state=new src-address-list=telnet_stage1 action=add-src-to-address-list address-list=telnet_stage2 address-list-timeout=1m comment="" disabled=no add chain=input protocol=tcp dst-port=23 connection-state=new action=add-src-to-address-list address-list=telnet_stage1 address-list-timeout=1m comment="" disabled=no
To view the contents of your Blacklist, go to “/ip firewall address-list” and type “print” to see the contents.