alert tcp $EXTERNAL_NET 113 -> $SMTP_SERVERS 25 (msg:"GPL DELETED sendmail 8.6.9 exploit"; flow:to_server,established; content:"|0A|D/"; reference:arachnids,140; reference:bugtraq,2311; reference:cve,1999-0204; classtype:attempted-admin; sid:2100655; rev:9; metadata:created_at 2010_09_23, signature_severity Unknown, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_07_26;)