alert tcp $EXTERNAL_NET any -> any any (msg:"🐾 - 🔔 Suspicious answer - Possible DarkVision C2"; flow:to_client, stateless; flowbits:set,pptrls.darkvision; flowbits:isnotset,pptrls.darkvision; content:"|01 00 00 00|"; fast_pattern; startswith; content:"|00 00|"; endswith; target:dest_ip; reference:url,https://malpedia.caad.fkie.fraunhofer.de/details/win.darkvision_rat; metadata:attack_target Client_and_Server, signature_severity Major, affected_product Windows_XP_Vista_7_8_10_11_Server_32_64_Bit, mitre_tactic_id TA0011, mitre_tactic_name Command_and_Control, mitre_technique_id T1071.001, mitre_technique_name Application_Layer_Protocol_Web_Protocols, former_category MALWARE, malware_family DarkVision, created_at 2025_03_16, updated_at 2025_03_16; sid:3321428; rev:3; classtype:trojan-activity; noalert;)