alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Observed Buran Ransomware UA"; flow:established,to_server; http.user_agent; content:"|63 6f 63 6b|"; fast_pattern; nocase; http.header_names; content:!"|0d 0a|Referer|0d 0a|"; reference:md5,5a4384f5e18cfbd993a135301141243e; classtype:command-and-control; sid:2029176; rev:5; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2019_12_16, deployment Perimeter, deprecation_reason Relevance, confidence High, signature_severity Major, tag Ransomware, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_08, mitre_tactic_id TA0040, mitre_tactic_name Impact, mitre_technique_id T1486, mitre_technique_name Data_Encrypted_for_Impact;)