alert http $HTTP_SERVERS any -> $EXTERNAL_NET any (
msg:"ET WEB_SERVER Generic Webshell Accessed on Internal Compromised Server";
flow:established,to_client;
file.data;
content:"<head/><form method=|22|post|22 20|action="; depth:34; nocase; fast_pattern;
content:"<input type=|22|input|22 20|name=|22|f_pp|22 20|value="; distance:0;
classtype:web-application-attack;
sid:2031472; rev:2;
metadata:affected_product Web_Server_Applications, attack_target Web_Server, created_at 2021_01_04, deployment Perimeter, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_01_04;
)