alert ip [176.65.138.0/24,176.65.139.0/24,176.65.142.0/24,176.65.143.0/24,176.65.148.0/22,176.65.149.0/24,176.98.187.0/24,176.120.22.0/24,176.126.192.0/23,176.126.194.0/24,176.223.116.0/23,176.223.118.0/24,177.234.136.0/21,178.16.52.0/22,178.20.210.0/24,178.236.252.0/24,179.43.175.0/24,179.61.197.0/24,180.178.160.0/24,180.178.192.0/18] any -> $HOME_NET any (msg:"ET DROP Spamhaus DROP Listed Traffic Inbound group 37"; 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:2400036; rev:4813; metadata:affected_product Any, attack_target Any, deployment Perimeter, tag Dshield, signature_severity Minor, created_at 2010_12_30, updated_at 2026_08_28;)