alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Ragnarok Ransomware CnC Activity M1"; flow:established,to_server; http.start; bsize:22; content:"GET /START_ HTTP/1.1|0d 0a|"; reference:url,twitter.com/malwrhunterteam/status/1256263426441125888; reference:md5,32ed52d918a138ddad24dd3a84e20e56; classtype:command-and-control; sid:2030116; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2020_05_06, deployment Perimeter, confidence High, signature_severity Major, tag Ransomware, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_05_06, mitre_tactic_id TA0040, mitre_tactic_name Impact, mitre_technique_id T1486, mitre_technique_name Data_Encrypted_for_Impact;)