alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Cobalt Strike Activity (GET)"; flow:established,to_server; http.request_line; content:"GET /9Wla HTTP/1.1"; fast_pattern; http.host; pcre:"/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/"; http.header_names; content:!"Referer"; reference:md5,ac45cc9b586d30836bb2997745a5208e; reference:url,twitter.com/malwrhunterteam/status/1455885521905934339; classtype:trojan-activity; sid:2034347; rev:1; metadata:attack_target Client_Endpoint, created_at 2021_11_05, deployment Perimeter, confidence Medium, signature_severity Major, tag c2, updated_at 2021_11_05, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;)