alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Agent-TMF Checkin"; flow:established,to_server; http.method; content:"GET"; http.uri; content:".php?gd="; fast_pattern; pcre:"/.php\?gd=\d+_\d+_\d+$/"; http.header_names; to_lowercase; content:!"|0d 0a|user-agent|0d 0a|"; content:!"|0d 0a|referer|0d 0a|"; classtype:command-and-control; sid:2013701; rev:4; metadata:created_at 2011_09_28, signature_severity Major, updated_at 2024_04_27;)