alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE OSX/Shlayer CnC Activity M4"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/sd/?c="; depth:7; fast_pattern; pcre:"/^(?:[A-Z0-9+/]{4})*(?:[A-Z0-9+/]{2}==|[A-Z0-9+/]{3}=|[A-Z0-9+/]{4})/Ri"; content:"&u="; distance:0; content:"&s="; distance:0; content:"&o="; distance:0; content:"&b="; distance:0; pcre:"/^\d{3,15}$/R"; reference:url,www.carbonblack.com/2019/02/12/tau-threat-intelligence-notification-new-macos-malware-variant-of-shlayer-osx-discovered/; classtype:command-and-control; sid:2026913; rev:2; metadata:affected_product Mac_OSX, attack_target Client_Endpoint, created_at 2019_02_14, deployment Perimeter, malware_family Shlayer, performance_impact Low, confidence High, signature_severity Major, updated_at 2020_08_27;)