alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Cobalt Strike Malleable C2 (MSDN Query Profile)"; flow:established,to_server; http.method; content:"GET"; http.uri; content:!"&ac="; content:!"&refinement="; content:"/Search/en-US?query="; content:"&pgArea=header"; distance:150; endswith; content:!"."; pcre:"/^\/Search\/en-US\?query=[a-z]{200,400}&pgArea=header$/"; http.accept; bsize:63; content:"text|2f|html|2c|application|2f|xhtml|2b|xml|2c|application|2f|xml|3b|q|3d|0|2e|9|2c 2a 2f 2a 3b|q|3d|0|2e|8"; fast_pattern; http.cookie; content:"MUID="; startswith; content:"|3b|"; distance:32; within:1; endswith; http.header_names; to_lowercase; content:!"|0d 0a|referer|0d 0a|"; classtype:command-and-control; sid:2032747; rev:3; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2020_10_13, deployment Perimeter, deployment SSLDecrypt, malware_family Cobalt_Strike, malware_family Cobalt_Strike, performance_impact Moderate, confidence Medium, signature_severity Major, updated_at 2024_05_01, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1001, mitre_technique_name Data_Obfuscation;)