Unusual Web Server Command Execution

Last updated 3 days ago on 2025-12-02
Created 3 days ago on 2025-12-02

About

This rule leverages the "new_terms" rule type to detect unusual command executions originating from web server processes on Linux systems. Attackers may exploit web servers to maintain persistence on a compromised system, often resulting in atypical command executions. As command execution from web server parent processes is common, the "new_terms" rule type approach helps to identify deviations from normal behavior.
Tags
Domain: EndpointDomain: WebOS: LinuxUse Case: Threat DetectionTactic: PersistenceData Source: Elastic DefendLanguage: kuery
Severity
medium
Risk Score
47
MITRE ATT&CK™

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

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

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

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

Definition

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

endpoint(opens in a new tab or window)

Query
event.category:process and host.os.type:linux and event.type:start and event.action:exec and (
  process.parent.name:(
    "apache" or "nginx" or "apache2" or "httpd" or "lighttpd" or "caddy" or "mongrel_rails" or "haproxy" or
    "gunicorn" or "uwsgi" or "openresty" or "cherokee" or "h2o" or "resin" or "puma" or "unicorn" or "traefik" or "uvicorn" or
    "tornado" or "hypercorn" or "daphne" or "twistd" or "yaws" or "webfsd" or "httpd.worker" or "flask" or "rails" or "mongrel" or
    php* or ruby* or perl* or python* or "node" or "java"
  ) or
  user.name:("apache" or "www-data" or "httpd" or "nginx" or "lighttpd" or "tomcat" or "tomcat8" or "tomcat9") or
  user.id:("33" or "498" or "48" or "54321")
) and process.working_directory:(
  /var/www/* or
  /usr/share/nginx/* or
  /srv/www/* or
  /srv/http/* or
  */webapps/* or
  /home/*/public_html/* or
  /home/*/www/* or
  /opt/* or
  /u0*/*
) and
process.command_line:* and process.name:(bash or dash or sh or tcsh or csh or zsh or ksh or fish) and process.args:"-c" and
not (
  (process.parent.name:java and not process.parent.executable:/u0*/*) or
  (process.parent.name:python* and process.parent.executable:(/bin/python* or /usr/bin/python* or /usr/local/bin/python* or /tmp/*python* or /opt/oracle.ahf/python/*)) or
  (process.parent.name:ruby* and process.parent.executable:(/bin/ruby* or /usr/bin/ruby* or /usr/local/bin/ruby* or /tmp/*ruby* or /bin/ruby or /usr/bin/ruby or /usr/local/bin/ruby)) or
  (process.parent.name:perl* and process.parent.executable:(/bin/perl* or /usr/bin/perl* or /usr/local/bin/perl* or /tmp/*perl* or /bin/perl or /usr/bin/perl or /usr/local/bin/perl)) or
  (process.parent.name:php* and process.parent.executable:(/bin/php* or /usr/bin/php* or /usr/local/bin/php* or /tmp/*php* or /bin/php or /usr/bin/php or /usr/local/bin/php)) or
  (process.parent.name:node and process.parent.executable:(/home/*/.vscode-server/* or /users/*/.vscode-server/* or /bin/node or /usr/bin/node or /usr/local/bin/node or /opt/plesk/node/*/bin/node)) or
  process.working_directory:(/u0*/*/sysman/emd or /u0*/app/oracle/product/*/dbhome_* or /u0*/app/oracle/product/*/db_* or /var/www/*edoc*) or
  process.parent.executable:/tmp/* or
  process.args:/usr/local/bin/wkhtmltopdf*
)

Install detection rules in Elastic Security

Detect Unusual Web Server Command Execution 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(opens in a new tab or window).