alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Win32/Kelihos.F exe Download 2"; flow:to_server,established; urilen:<13; http.method; content:"GET"; http.uri; content:".exe"; fast_pattern; endswith; pcre:"/^\/[^\x2f]+?\.exe$/i"; http.host; content:".ru"; endswith; http.header; content:".ru|0d 0a|Cache-Control|3a 20|no-cache|0d 0a|"; distance:0; http.header_names; content:"|0d 0a|User-Agent|0d 0a|Host|0d 0a|Cache-Control|0d 0a 0d 0a|"; startswith; reference:md5,1303188d039076998b170fffe48e4cc0; classtype:trojan-activity; sid:2017190; rev:8; metadata:created_at 2013_07_24, malware_family Win32_Kelihos_F, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_09_29;)