alert dns $HOME_NET any -> any any (msg:"ET RETIRED CopyKittens Matryoshka DNS Lookup 1 (winupdate64 . com)"; dns.query; content:"winupdate64.com"; depth:15; nocase; endswith; fast_pattern; reference:url,www.clearskysec.com/wp-content/uploads/2017/07/Operation_Wilted_Tulip.pdf; classtype:trojan-activity; sid:2024495; rev:7; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2017_07_25, deployment Perimeter, former_category MALWARE, malware_family Matryoshka, performance_impact Moderate, confidence Medium, signature_severity Major, updated_at 2024_09_16, reviewed_at 2024_09_16;)