alert dns $HOME_NET any -> any any (msg:"ET INFO DYNAMIC_DNS Query to a *.spanishlearning .com .ar Domain"; dns.query; content:".spanishlearning.com.ar"; fast_pattern; nocase; endswith; reference:url,freedns.afraid.org/domain/registry/page-4.html; classtype:bad-unknown; sid:2053066; rev:2; metadata:attack_target Client_and_Server, created_at 2024_05_30, deployment Perimeter, performance_impact Low, confidence High, signature_severity Informational, updated_at 2024_06_11, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1568, mitre_technique_name Dynamic_Resolution;)