alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Backdoor.Graybird Checkin"; flow:to_server,established; http.uri; content:"/count.asp?mac="; content:"&os="; content:"&av="; http.user_agent; content:"Post"; depth:4; endswith; reference:md5,0fd68129ecbf68ad1290a41429ee3e73; reference:md5,11353f5bdbccdd59d241644701e858e6; classtype:command-and-control; sid:2014365; rev:5; metadata:created_at 2012_02_11, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_10_13;)