alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET HUNTING Observed Suspicious Request nc.exe in URI"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/nc.exe"; fast_pattern; nocase; endswith; http.header_names; content:!"Referer"; classtype:bad-unknown; sid:2033891; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_09_02, deployment Perimeter, confidence Medium, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_09_02;)