Unusual File Creation via Web Server

Last updated 15 days ago on 2026-08-19
Created a month ago on 2026-07-24

About

This rule leverages the "new_terms" rule type to detect unusual file creations originating from web server processes on Linux systems. Attackers may exploit web servers to maintain persistence on a compromised system, often resulting in atypical file creations. As file creations from web server processes are common, the "new_terms" rule type approach helps to identify deviations from normal behavior.
Tags
Domain: EndpointDomain: WebOS: LinuxUse Case: Threat DetectionTactic: PersistenceTactic: ExecutionTactic: Command and ControlTactic: Initial AccessData Source: Elastic DefendLanguage: kuery
Severity
low
Risk Score
21
MITRE ATT&CK™

Persistence (TA0003)(external, opens in a new tab or window)

Execution (TA0002)(external, opens in a new tab or window)

Command and Control (TA0011)(external, opens in a new tab or window)

Initial Access (TA0001)(external, opens in a new tab or window)

License
Elastic License v2(external, opens in a new tab or window)

Definition

Rule Type
New Terms Rule
Integration Pack
Prebuilt Security Detection Rules
Index Patterns
logs-endpoint.events.file*
Related Integrations

endpoint(external, opens in a new tab or window)

Query
text code block:
event.category:file and host.os.type:linux and event.action:(creation or rename) and ( process.name: ( "nginx" or "apache2" or "httpd" or "caddy" or "lighttpd" or "httpd.worker" or "httpd-worker" or "httpd-prefork" or "php-cgi" or "php-fcgi" or "php-cgi.cagefs" or "frankenphp" or "lshttpd" or "litespeed" or "openlitespeed" or "fcgiwrap" or "uwsgi" or "daphne" or "uvicorn" or "hypercorn" or "granian" or "waitress-serve" or "flask" or "puma" or "unicorn" or "unicorn_rails" or "thin" or "rackup" or "mongrel_rails" or "starman" or "plackup" or "twiggy" or "hypnotoad" or "starlet" or "unitd" or "unitd-debug" or php-fpm* or lsphp* or gunicorn* or "nginx3" or "apache" or *.cgi or *.fcgi ) or (process.name: "java" and file.extension: ("jsp" or "jspx" or "jspf" or "tag" or "tagx" or "war" or "ear")) or (process.name: ("node" or "nodejs") and file.extension: ("js" or "mjs" or "cjs" or "ts" or "mts" or "cts")) or (process.name: "dotnet" and file.extension: ("cshtml" or "razor")) or (process.name: (mono* or xsp* or mod-mono-server* or fastcgi-mono-server*) and file.extension: ("asp" or "aspx" or "ashx" or "asmx" or "ascx" or "cshtml")) or (process.name: python* and file.extension: ("wsgi" or "cgi" or "fcgi")) or (process.name: ruby* and file.extension: ("erb" or "ru")) or (process.name: perl* and file.extension: ("cgi" or "fcgi" or "psgi")) or (process.name: lua* and file.extension: ("lua" or "luac")) ) and file.path:( /home/*/* or /var/www/* or /srv/www/* or /srv/http/* or /usr/share/nginx/* or /opt/zimbra/jetty* or /usr/share/caddy/* or /usr/local/lsws/* or /opt/bitnami/* or */sites/*/files/* or /opt/easyengine/* or */wp-content/* or */httpdocs/* or */httpsdocs/* or */htdocs/* or */wwwroot/* or */webroot/* or */cgi-bin/* or */upload/* or */uploads/* or */images/* or */media/* or */userfiles/* or */attachments/* or /usr/share/webapps/* or /usr/share/zabbix/* or /usr/share/phpmyadmin/* or /usr/share/phpMyAdmin/* or /var/lib/roundcube/* or /usr/share/cacti/* or /usr/share/nagios* or /var/lib/tomcat* or /usr/share/tomcat* or /usr/local/tomcat/* or /opt/tomcat* or /var/lib/jetty* or /usr/share/jetty* or /usr/local/cpanel/* or /usr/local/psa* or /opt/psa/admin/* or /usr/share/webmin/* or /usr/libexec/webmin/* or /usr/local/nginx/* or /usr/local/apache* or /usr/sap/* or /opt/rh/* or */public_html/* or */private_html/* or */public/* or */private/* or */deployments/* or */autodeploy/* or */dropins/* or */installedApps/* or /srv/caddy/* or /usr/local/openresty/* or */fileadmin/* or */custom_apps/* or */vhost* or /opt/apache-tomcat* or /opt/jetty* or /usr/local/jetty* or */wildfly*/* or */jboss*/* or */glassfish/* or */user_projects/domains/* or */resin*/webapps/* or */installedApps/* ) and not ( file.path:*/storage/framework/sessions/* or (process.name:php-fpm* and file.path:(/mnt/WEB/*/public_html/tmp/templates/frontend/*.php or /mnt/WEB/*/public_html/wp-content/languages/*.json)) or (process.name:node and (user.id>=1000 or user.id:0)) )

Install detection rules in Elastic Security

Detect Unusual File Creation via Web Server in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(external, opens in a new tab or window).