alert tcp $EXTERNAL_NET any -> $HOME_NET 110 (msg:"GPL DELETED qpopper overflow"; flow:to_server,established; content:"|E8 D9 FF FF FF|/bin/sh"; reference:bugtraq,830; reference:cve,1999-0822; reference:nessus,10184; classtype:attempted-admin; sid:2100290; rev:11; metadata:created_at 2010_09_23, signature_severity Unknown, updated_at 2019_07_26;)