alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE GOLDBACKDOOR Domain (main .dailynk .us) in TLS SNI"; flow:established,to_server; tls.sni; bsize:15; content:"main.dailynk.us"; fast_pattern; reference:url,stairwell.com/wp-content/uploads/2022/04/Stairwell-threat-report-The-ink-stained-trail-of-GOLDBACKDOOR.pdf; classtype:targeted-activity; sid:2036371; rev:3; metadata:attack_target Client_Endpoint, created_at 2022_04_25, deployment Perimeter, deprecation_reason Relevance, malware_family GOLDBACKDOOR, performance_impact Low, confidence High, signature_severity Major, updated_at 2024_03_26;)