alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Cobalt Strike Related Activity (GET)"; flow:established,to_server; http.method; content:"GET"; http.uri; bsize:3; content:"/cm"; http.user_agent; bsize:78; content:"Mozilla/5.0 (compatible|3b 20|MSIE 9.0|3b 20|Windows NT 6.1|3b 20|Trident/5.0|3b 20|BOIE9|3b|ENUSMSE)"; fast_pattern; http.header_names; to_lowercase; content:!"|0d 0a|referer|0d 0a|"; http.host; pcre:"/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/"; reference:url,thedfirreport.com/2022/05/09/seo-poisoning-a-gootloader-story/; classtype:trojan-activity; sid:2036677; rev:3; metadata:attack_target Client_Endpoint, created_at 2022_05_25, deployment Perimeter, deployment SSLDecrypt, malware_family Cobalt_Strike, confidence Medium, signature_severity Major, updated_at 2024_04_30, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1001, mitre_technique_name Data_Obfuscation;)