alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Win32/Aibatook checkin"; flow:established,to_server; http.method; content:"POST"; http.uri; content:".asp"; pcre:"/\.asp$/"; http.request_body; content:"m="; depth:2; content:"AA=="; fast_pattern; pcre:"/^m=(?:[A-Za-z0-9+/]{4}){11}(?:(?:[A-Za-z0-9+/]{4}){6})?AA==/i"; http.header_names; content:!"Referer|0d 0a|"; content:!"Accept"; reference:md5,57a0af91f3b35ef1cf54502e77cc2904; reference:url,www.welivesecurity.com/2014/07/16/win32aibatook/; classtype:command-and-control; sid:2018685; rev:5; metadata:created_at 2014_07_16, malware_family Win32_Aibatook, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_10_05;)