alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Agent.BAAB Checkin"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/debug/trace/"; fast_pattern; pcre:"/^\/debug\/trace\/(?:Fw(?:Downloaded|Check)|N(?:oFw|sis))$/"; http.user_agent; content:"NSISDL/1.2|20|(Mozilla)"; depth:20; http.header_names; content:!"Referer"; content:"Accept"; reference:md5,406fea6262d8ee05e0ab4247c1083443; reference:url,www.virustotal.com/en/file/b0baed750f09ff058e5bd28d6443da833496dc1d1ed674ee6b2caf91889f648e/analysis/1389133969/; classtype:command-and-control; sid:2017946; rev:5; metadata:created_at 2014_01_08, signature_severity Major, updated_at 2020_08_18;)