alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE MSIL/Matrix Ransomware CnC Activity"; flow:established,to_server; http.method; content:"GET"; http.uri; content:".php?apikey="; content:"&compuser="; distance:0; content:"&sid="; distance:0; content:"&phase="; distance:0; http.user_agent; content:"Mozilla/4.0 (compatible|3b 20|Synapse)"; fast_pattern; bsize:33; http.header_names; content:!"Referer|0d 0a|"; reference:md5,ad8a7a383971ce0f5fc51e909e406996; classtype:command-and-control; sid:2024120; rev:3; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2017_02_24, deployment Perimeter, malware_family Ransomware, malware_family Matrix, confidence High, signature_severity Major, tag Ransomware, updated_at 2020_08_04, mitre_tactic_id TA0040, mitre_tactic_name Impact, mitre_technique_id T1486, mitre_technique_name Data_Encrypted_for_Impact;)