alert dns $HOME_NET any -> any any (msg:"ET DYN_DNS Observed DNS Query to DynDNS Domain (publicvm .com)"; dns.query; content:".publicvm.com"; nocase; endswith; content:!"www.publicvm.com"; reference:url,dnsexit.com/domains/free-second-level-domains/; classtype:bad-unknown; sid:2034457; rev:3; metadata:affected_product Any, attack_target Client_Endpoint, created_at 2021_11_15, deployment Perimeter, former_category POLICY, performance_impact Low, confidence High, signature_severity Informational, updated_at 2024_06_11;)