ET WEB_SERVER Generic Webshell Accessed

alert http $EXTERNAL_NET any -> $HTTP_SERVERS any (
    msg:"ET WEB_SERVER Generic Webshell Accessed";
    flow:established,to_server;
    http.method;
    content:"POST";
    http.uri;
    content:".php"; endswith;
    http.referer;
    content:".php"; endswith;
    http.request_body;
    content:"password="; startswith;
    content:"&action=login&hide="; fast_pattern; distance:0;
    content:"&username="; distance:0;
    reference:url,blog.trendmicro.com/trendlabs-security-intelligence/ensiko-a-webshell-with-ransomware-capabilities/;
    classtype:web-application-attack;
    sid:2030650; rev:1;
    metadata:attack_target Web_Server, created_at 2020_08_05, deployment Perimeter, performance_impact Low, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_08_05;
)