alert tcp-stream $EXTERNAL_NET 1024: -> $HOME_NET any (msg:"ET MALWARE Win32/Agent.UHC CnC Activity"; flow:established,to_client; stream_size:client,<,40; content:"|2e 2e 61 58 63 66|"; fast_pattern; reference:md5,042261407926beaaf0e3ed8bba5307cc; classtype:command-and-control; sid:2034219; rev:3; metadata:attack_target Client_Endpoint, created_at 2021_10_18, deployment Perimeter, malware_family Win32_Agent_UHC, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2022_02_28;)