alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"🐾 - 🚨 QuasarRAT 🪟 TLS Certificate - 👿 Malicious C2 activity"; flow:to_client, stateless; tls.cert_issuer; content:"CN=Quasar Server CA Server"; fast_pattern; reference:url,https://attack.mitre.org/tactics/TA0011/; reference:url,https://malpedia.caad.fkie.fraunhofer.de/details/win.quasar_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 QuasarRAT, created_at 2025_01_04, updated_at 2025_01_04; sid:3321409; rev:1; classtype:command-and-control;)