Da preprečimo “brute-force” napad na SSH oziroma FTP na Mikrotik usmerjevalniku, je treba v konfiguracijo RouterOS vnesti naslednje vrstice, zaradi katerih bo dovoljenih le 10 nepravilnih vnosov gesel na minuto. Vnesemo jih v polje /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
Naslednje vrstice pa bodo blokirale SSH “broute-force” za 10 dni.
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 add chain=forward protocol=tcp dst-port=22 src-address-list=ssh_blacklist action=drop \ comment=”drop ssh brute downstream” disabled=no
Če bi si radi ogledali seznam blokiranih IPjev, si to lahko ogledate tako, da v terminal vpišete naslednji ukaz:
“/ip firewall address-list” in nato “print“