alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Havex RAT CnC Server Response"; flow:established,from_server; http.header; content:!"Keep-Alive|3a 20|"; nocase; content:!"Conncection|3a 20|Keep-Alive"; nocase; file_data; content:"|3c 21 2d 2d|havexhavex|2d 2d 3e|"; reference:md5,6557d6518c3f6bcb8b1b2de77165c962; classtype:command-and-control; sid:2018243; rev:3; metadata:created_at 2014_03_11, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_09_30;)