alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET EXPLOIT_KIT CoolEK Payload Download (5)"; flow:established,to_server; http.uri; content:".txt?e="; nocase; fast_pattern; pcre:"/\.txt\?e=\d+(?:&[fh]=\d+)?$/"; http.header_names; content:!"Referer|0d 0a|"; classtype:exploit-kit; sid:2016414; rev:10; metadata:created_at 2013_02_16, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_09_18;)