alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Enfal CnC POST"; flow:to_server,established; http.method; content:"POST"; http.uri; content:".cgi"; fast_pattern; endswith; http.header; pcre:"/^Host\x3a[^\r\n]+\r\nContent-Length\x3a\x20\d+\r\n(?:Cache-Control|Pragma)\x3a\x20no-cache\r\n(?:\r\n)?$/mi"; http.header_names; content:!"User-Agent|0d 0a|"; content:!"Referer|0d 0a|"; content:!"Content-Type|0d 0a|"; reference:md5,f1b341d3383b808ecfacfa22dcbe9196; classtype:command-and-control; sid:2021079; rev:6; metadata:created_at 2015_05_09, performance_impact Significant, signature_severity Major, updated_at 2024_03_25;)