alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE W32/Einstein CnC Checkin"; flow:established,to_server; http.method; content:"POST"; nocase; http.uri; content:"/"; content:".php?id="; distance:5; within:8; content:"&ext="; fast_pattern; pcre:"/\x2f[a-z]{5}\x2Ephp\x3fid\x3d/"; reference:url,www.cyberesi.com/2011/10/06/trojan-matryoshka-and-trojan-einstein/; classtype:command-and-control; sid:2013767; rev:4; metadata:created_at 2011_10_12, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_03_17;)