alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Possible Ransomware HTTP POST to Onion Link Domain"; flow:established,to_server; http.method; content:"POST"; http.host; content:".onion.link"; endswith; fast_pattern; http.request_body; content:"data="; reference:url,us-cert.cisa.gov/ncas/alerts/aa21-076a; classtype:command-and-control; sid:2032219; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_03_19, deployment Perimeter, confidence Medium, signature_severity Major, tag Ransomware, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_03_19, mitre_tactic_id TA0040, mitre_tactic_name Impact, mitre_technique_id T1486, mitre_technique_name Data_Encrypted_for_Impact;)