alert dns $HOME_NET any -> any any (msg:"ET MALWARE Observed Adwind RAT CnC DNS Query"; dns.query; content:"21736.xyz"; nocase; endswith; pcre:"/(?:^|\.)21736\.xyz$/"; reference:url,research.checkpoint.com/2020/the-turkish-rat-distributes-evolved-adwind-in-a-massive-ongoing-phishing-campaign/; classtype:domain-c2; sid:2029536; rev:3; metadata:attack_target Client_Endpoint, created_at 2020_02_25, deployment Perimeter, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_11_02;)