This is a blocklist I use with on my Mikrotik router to block all connections from known spam/criminal/etc. networks.

Every couple days I pull lists from:

• Spamhaus (DROP & EDROP)
• dShield
• blacklist.de (all.txt)
• EmergingThreats compromised IP

and reformat it to allow automatic import to MT routers.

Run following to your MT device with not less that 7d schedule:

Download script:
/tool fetch url="https://raw.githubusercontent.com/pwlgrzs/Mikrotik-Blacklist/master/blacklist.rsc" mode=https
Install script:
/ip firewall address-list remove [find where comment="blacklist"]; /import file-name=blacklist.rsc

You'll also need firewall rule:
/ip firewall filter add chain=input action=drop connection-state=new src-address-list=blacklist in-interface=IFNAME
Note: Replace IFNAME in-interface name with one you have configured

Check out more detailed instructions here.

You can also import install.rsc file, it will do all of above for you.
Upload to MT and run /import file-name=install.rsc in terminal. You still need to manually add firewall rule.

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