alert ip [23.147.148.0/24,23.147.156.0/24,23.147.164.0/24,23.148.144.0/24,23.164.152.0/24,23.164.153.0/24,23.172.112.0/24,23.176.184.0/24,23.235.128.0/19,23.247.176.0/22,24.137.16.0/20,24.170.208.0/20,24.233.0.0/19,24.236.0.0/19,27.50.63.0/24,27.99.128.0/17,27.100.28.0/22,27.112.32.0/19,27.122.32.0/20,27.123.208.0/22] any -> $HOME_NET any (msg:"ET DROP Spamhaus DROP Listed Traffic Inbound group 2"; reference:url,www.spamhaus.org/drop/drop.txt; threshold:type limit, track by_src, seconds 3600, count 1; classtype:misc-attack; flowbits:set,ET.Evil; flowbits:set,ET.DROPIP; sid:2400001; rev:4770; metadata:affected_product Any, attack_target Any, deployment Perimeter, tag Dshield, signature_severity Minor, created_at 2010_12_30, updated_at 2026_07_16;)