alert dns $HOME_NET any -> any any (msg:"ET INFO DYNAMIC_DNS Query to a *.sytes.net Domain"; dns.query; content:".sytes.net"; fast_pattern; nocase; endswith; reference:url,www.trendmicro.com/en_us/research/23/b/earth-kitsune-delivers-new-whiskerspy-backdoor.html; classtype:bad-unknown; sid:2044233; rev:12; metadata:attack_target Client_and_Server, created_at 2012_03_05, deployment Perimeter, performance_impact Low, confidence High, signature_severity Informational, updated_at 2024_12_01, reviewed_at 2024_04_25, former_sid 2804633, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1568, mitre_technique_name Dynamic_Resolution;)