alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET CURRENT_EVENTS [Fireeye] Backdoor.HTTP.GORAT.[SID1]"; flow:established,to_server; http.start; content:"|0d 0a|Cookie: SID1="; fast_pattern; http.method; content:"GET"; http.header_names; content:!"Referer"; content:!"Accept"; reference:url,github.com/fireeye/red_team_tool_countermeasures; classtype:trojan-activity; sid:2031278; rev:3; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2020_12_08, deployment Perimeter, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_12_09;)