alert tcp $EXTERNAL_NET any -> $HOME_NET 1020 (msg:"GPL DELETED Vampire 1.2 connection request"; flow:to_server,established; content:"Hello..."; depth:8; flowbits:set,backdoor.vampire_12.connect; flowbits:noalert; classtype:misc-activity; sid:2103063; rev:4; metadata:created_at 2010_09_23, signature_severity Unknown, updated_at 2019_07_26;)