ET WEB_SERVER Generic Mailer Accessed on Internal Compromised Server

alert http $HTTP_SERVERS any -> $EXTERNAL_NET any (
    msg:"ET WEB_SERVER Generic Mailer Accessed on Internal Compromised Server";
    flow:established,to_client;
    file.data;
    content:">EMAIl|3a|"; nocase;
    content:"SUBJECT|3a 20|<input name=|22|assunto|22|"; nocase; distance:0;
    content:"type=|22|submit|22 20|name=|22|Enoc|22 20|value=|22|FIRE DOWN|22|"; nocase; distance:0; fast_pattern;
    classtype:web-application-attack;
    sid:2031513; rev:2;
    metadata:affected_product Web_Server_Applications, attack_target Web_Server, created_at 2021_01_12, deployment Perimeter, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_01_12;
)