alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Citadel Activity POST"; flow:to_server,established; urilen:15; http.method; content:"POST"; http.uri; content:"/pk/request.flv"; http.header_names; content:!"Content-Type|0d 0a|"; content:!"Referer|0d 0a|"; reference:md5,a354873df6dbce59e801380cee39ac17; classtype:trojan-activity; sid:2017582; rev:5; metadata:created_at 2013_10_12, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_04_28;)