alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Malicious JS.Nemucod to PS Dropping PE Nov 14 M2"; flow:to_server,established; http.method; content:"GET"; http.uri; content:".php?f="; fast_pattern; pcre:"/^\/\w+\.php\?f=[a-z]?\d{1,3}(?:\.(?:dat|gif))?$/"; http.user_agent; content:"Mozilla/4.0 (compatible|3b 20|MSIE 7.0|3b|"; startswith; http.header_names; content:!"Referer"; reference:md5,551c440d76be5ab9932d8f3e8f65726e; classtype:trojan-activity; sid:2023754; rev:8; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2016_11_28, deployment Perimeter, performance_impact Low, signature_severity Major, updated_at 2020_10_08;)