alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Jaff Ransomware Checkin M1"; flow:to_server,established; urilen:4; http.request_line; content:"GET /a5/ HTTP/1."; depth:16; fast_pattern; http.header_names; content:"|0d 0a|Host|0d 0a 0d 0a|"; depth:10; endswith; reference:md5,924c84415b775af12a10366469d3df69; reference:url,blog.dynamoo.com/2017/05/malware-spam-with-nmpdf-attachment.html; classtype:command-and-control; sid:2024290; rev:4; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2017_05_11, deployment Perimeter, malware_family Jaff_Ransomware, confidence High, signature_severity Major, tag Ransomware, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_11_05, mitre_tactic_id TA0040, mitre_tactic_name Impact, mitre_technique_id T1486, mitre_technique_name Data_Encrypted_for_Impact;)