alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Crpx0 Ransomware User-Agent Observed"; flow:established,to_server; http.user_agent; content:"crpx0-client/"; startswith; classtype:command-and-control; sid:2068536; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, tls_state TLSDecrypt, created_at 2026_04_02, deployment Perimeter, deployment SSLDecrypt, confidence High, signature_severity Critical, updated_at 2026_04_02, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol; target:src_ip;)