alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Win32/Hyteod CnC Beacon"; flow:established,to_server; http.method; content:"GET"; http.header; content:"|5f 5e 5b 8b e5 5d|"; fast_pattern; http.user_agent; content:"Mozilla/5.0 (compatible|3b 20|MSIE 9.0|3b 20|Windows NT 6.1|3b 20|Trident/5.0)"; bsize:63; http.content_type; content:"application/x-www-form-urlencoded"; bsize:33; http.header_names; content:!"Accept-"; content:!"Connection|0d 0a|"; content:!"Referer|0d 0a|"; reference:md5,f2ad19a08063171b039accd24b0c27ca; classtype:command-and-control; sid:2020821; rev:4; metadata:attack_target Client_Endpoint, created_at 2015_03_31, deployment Perimeter, malware_family Win32_Hyteod, confidence Medium, signature_severity Major, tag c2, updated_at 2020_09_29, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;)