alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Observed CrimsonRAT Domain (waqers .duckdns .org in TLS SNI)"; flow:established,to_server; tls.sni; bsize:18; content:"waqers.duckdns.org"; fast_pattern; reference:url,twitter.com/0xrb/status/1795362130281324685; classtype:trojan-activity; sid:2052910; rev:1; metadata:attack_target Client_Endpoint, created_at 2024_05_28, deployment Perimeter, malware_family CrimsonRAT, confidence High, signature_severity Major, updated_at 2024_05_28, reviewed_at 2024_06_27, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)