alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE TA450 CnC Activity - Victim Requesting Commands (GET)"; flow:established,to_server; flowbits:isset,ET.TA450.Auth; urilen:8; http.method; content:"GET"; http.uri; content:"/command"; fast_pattern; http.header_names; content:"|0d 0a|x-cookie|0d 0a|"; nocase; content:!"|0d 0a|referer|0d 0a|"; nocase; http.content_type; content:"application/json"; http.header; content:"x-cookie|3a 20|"; nocase; pcre:"/^\d{1,3}[\r\n]/R"; reference:md5,64e7e2d2e037d21e8564de52061a31c7; classtype:command-and-control; sid:2064091; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, tls_state TLSDecrypt, created_at 2025_08_21, deployment Perimeter, deployment SSLDecrypt, confidence High, signature_severity Critical, tag c2, tag TA450, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2025_08_21, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol; target:src_ip;)