alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Fileless infection dropped by EK CnC Beacon"; flow:established,to_server; http.uri; content:"hl="; content:"source="; content:"aq="; content:"aqi="; content:"aql="; fast_pattern; content:"oq="; http.content_type; bsize:33; content:"application/x-www-form-urlencoded"; http.header; content:!"google."; http.header_names; strip_pseudo_headers; to_lowercase; content:!"|0d 0a|user-agent|0d 0a|"; content:!"|0d 0a|accept"; content:!"|0d 0a|referer|0d 0a|"; content:"|0d 0a|content-type|0d 0a|"; startswith; classtype:command-and-control; sid:2020734; rev:6; metadata:attack_target Client_Endpoint, created_at 2015_03_24, deployment Perimeter, performance_impact Moderate, confidence High, signature_severity Major, tag c2, updated_at 2024_05_04, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;)