alert http $HOME_NET any -> $EXTERNAL_NET any (
msg:"ET MALWARE Win32/CryptFile2 Ransomware Checkin M2";
flow:established,to_server;
http.method;
content:"POST";
http.uri;
content:".php"; endswith;
http.user_agent;
content:"|70 6f 73 74 5f 65 78 61 6d 70 6c 65|"; fast_pattern;
http.request_body;
content:"=0x";
content:"|2c|0x"; distance:2; within:5;
content:"|3c 62 72 3e|"; distance:0;
reference:md5,ad2c80611ebc7f6d45bd3e46de38b776;
reference:md5,5bb7d85f7a5f1d2b01efabe5635e2992;
classtype:command-and-control;
sid:2023397; rev:5;
metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2016_10_24, deployment Perimeter, malware_family Ransomware, malware_family CryptFile2, confidence Medium, signature_severity Major, tag Ransomware, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_03_11, mitre_tactic_id TA0040, mitre_tactic_name Impact, mitre_technique_id T1486, mitre_technique_name Data_Encrypted_for_Impact;
)