alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Win32/PSW.Steam.NBP Checkin"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/data2.php?file="; fast_pattern; http.user_agent; content:"Mozilla/4.0 (compatible|3b 20|Synapse)"; startswith; http.header_names; to_lowercase; content:!"|0d 0a|accept"; content:!"|0d 0a|referer|0d 0a|"; reference:md5,17d2b62f2fa20f407485437de17787fb; reference:md5,bec091077138a1cac49db00495d456e7; classtype:command-and-control; sid:2018949; rev:7; metadata:created_at 2014_08_18, malware_family Win32_PSW_Steam_NBP, signature_severity Major, updated_at 2024_05_01;)