[New Rule] Web Server Potential Command Injection Request

Author: Aegrah

rules/cross-platform/persistence_web_server_potential_command_injection.toml

@@ -0,0 +1,169 @@
+[metadata]
+creation_date = "2025/11/19"
+integration = ["nginx", "apache", "apache_tomcat", "iis", "network_traffic"]
+maturity = "production"
+updated_date = "2025/11/19"
+
+[rule]
+author = ["Elastic"]
+description = """
+This rule detects potential command injection attempts via web server requests by identifying URLs that contain
+suspicious patterns commonly associated with command execution payloads. Attackers may exploit vulnerabilities in web
+applications to inject and execute arbitrary commands on the server, often using interpreters like Python, Perl, Ruby,
+PHP, or shell commands. By monitoring for these indicators in web traffic, security teams can identify and respond to
+potential threats early.
+"""
+from = "now-61m"
+interval = "1h"
+language = "esql"
+license = "Elastic License v2"
+name = "Web Server Potential Command Injection Request"
+risk_score = 21
+rule_id = "f3ac6734-7e52-4a0d-90b7-6847bf4308f2"
+severity = "low"
+tags = [
+    "Domain Scope: Single",
+    "Domain: Web",
+    "OS: Linux",
+    "OS: macOS",
+    "OS: Windows",
+    "Use Case: Threat Detection",
+    "Tactic: Reconnaissance",
+    "Tactic: Credential Access",
+    "Data Source: Network Packet Capture",
+    "Data Source: Nginx",
+    "Data Source: Apache",
+    "Data Source: Apache Tomcat",
+    "Data Source: IIS",
+]
+timestamp_override = "event.ingested"
+type = "esql"
+query = '''
+from
+  logs-network_traffic.http-*,
+  logs-network_traffic.tls-*,
+  logs-nginx.access-*,
+  logs-apache.access-*,
+  logs-apache_tomcat.access-*,
+  logs-iis.access-*
+| where
+    @timestamp > now() - 1d and
+    (url.original is not null or url.full is not null)
+
+| eval esql_url_text  = case(url.original is not null, url.original, url.full)
+| eval esql_url_lower = to_lower(esql_url_text)
+
+| eval contains_interpreter = case(esql_url_lower like "*python* -c*" or esql_url_lower like "*perl* -e*" or esql_url_lower like "*ruby* -e*" or esql_url_lower like "*ruby* -rsocket*" or esql_url_lower like "*lua* -e*" or esql_url_lower like "*php* -r*" or esql_url_lower like "*node* -e*", 1, 0)
+| eval contains_shell = case(esql_url_lower like "*/bin/bash*" or esql_url_lower like "*bash*-c*" or esql_url_lower like "*/bin/sh*" or esql_url_lower rlike "*sh.{1,2}-c*", 1, 0)
+| eval contains_nc = case(esql_url_lower like "*netcat*" or esql_url_lower like "*ncat*" or esql_url_lower rlike """.*nc.{1,2}[0-9]{1,3}(\.[0-9]{1,3}){3}.{1,2}[0-9]{1,5}.*""" or esql_url_lower like "*nc.openbsd*" or esql_url_lower like "*nc.traditional*" or esql_url_lower like "*socat*", 1, 0)
+| eval contains_devtcp = case(esql_url_lower like "*/dev/tcp/*" or esql_url_lower like "*/dev/udp/*", 1, 0)
+| eval contains_helpers = case(esql_url_lower like "*mkfifo*" or esql_url_lower like "*nohup*" or esql_url_lower like "*setsid*" or esql_url_lower like "*busybox*", 1, 0)
+| eval contains_sus_cli = case(esql_url_lower like "*import*pty*spawn*" or esql_url_lower like "*import*subprocess*call*" or esql_url_lower like "*tcpsocket.new*" or esql_url_lower like "*tcpsocket.open*" or esql_url_lower like "*io.popen*" or esql_url_lower like "*os.execute*" or esql_url_lower like "*fsockopen*", 1, 0)
+| eval contains_privileges = case(esql_url_lower like "*chmod*" or esql_url_lower like "*chown*", 1, 0)
+| eval contains_downloader = case(esql_url_lower like "*curl *" or esql_url_lower like "*wget *" , 1, 0)
+| eval contains_file_read_keywords = case(esql_url_lower like "*/etc/shadow*" or esql_url_lower like "*/etc/passwd*" or esql_url_lower like "*/root/.ssh/*" or esql_url_lower like "*/home/*/.ssh/*" or esql_url_lower like "*~/.ssh/*" or esql_url_lower like "*/proc/self/environ*", 1, 0)
+| eval contains_base64_cmd = case(esql_url_lower like "*base64*-d*" or esql_url_lower like "*xxd*" or esql_url_lower like "*echo*|*base64*", 1, 0)
+| eval contains_suspicious_path = case(esql_url_lower like "*/tmp/*" or esql_url_lower like "*/var/tmp/*" or esql_url_lower like "*/dev/shm/*" or esql_url_lower like "*/root/*" or esql_url_lower like "*/home/*/*" or esql_url_lower like "*/var/www/*" or esql_url_lower like "*/etc/cron.*/*", 1, 0)
+
+| eval any_payload_keyword = case(
+    contains_interpreter == 1 or contains_shell == 1 or contains_nc == 1 or contains_devtcp == 1 or
+    contains_helpers == 1 or contains_sus_cli == 1 or contains_privileges == 1 or contains_downloader == 1 or
+    contains_file_read_keywords == 1 or contains_base64_cmd == 1 or contains_suspicious_path == 1, 1, 0)
+
+| keep
+    @timestamp,
+    esql_url_lower,
+    any_payload_keyword,
+    contains_interpreter,
+    contains_shell,
+    contains_nc,
+    contains_devtcp,
+    contains_helpers,
+    contains_sus_cli,
+    contains_privileges,
+    contains_downloader,
+    contains_file_read_keywords,
+    contains_base64_cmd,
+    contains_suspicious_path,
+    source.ip,
+    destination.ip,
+    agent.id,
+    http.request.method,
+    http.response.status_code,
+    user_agent.original
+
+| where any_payload_keyword == 1
+| limit 100
+'''
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+
+[[rule.threat.technique]]
+id = "T1505"
+name = "Server Software Component"
+reference = "https://attack.mitre.org/techniques/T1505/"
+
+[[rule.threat.technique.subtechnique]]
+id = "T1505.003"
+name = "Web Shell"
+reference = "https://attack.mitre.org/techniques/T1505/003/"
+
+[rule.threat.tactic]
+id = "TA0003"
+name = "Persistence"
+reference = "https://attack.mitre.org/tactics/TA0003/"
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+
+[[rule.threat.technique]]
+id = "T1059"
+name = "Command and Scripting Interpreter"
+reference = "https://attack.mitre.org/techniques/T1059/"
+
+[[rule.threat.technique.subtechnique]]
+id = "T1059.004"
+name = "Unix Shell"
+reference = "https://attack.mitre.org/techniques/T1059/004/"
+
+[rule.threat.tactic]
+id = "TA0002"
+name = "Execution"
+reference = "https://attack.mitre.org/tactics/TA0002/"
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+
+[[rule.threat.technique]]
+id = "T1071"
+name = "Application Layer Protocol"
+reference = "https://attack.mitre.org/techniques/T1071/"
+
+[rule.threat.tactic]
+id = "TA0011"
+name = "Command and Control"
+reference = "https://attack.mitre.org/tactics/TA0011/"
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+
+[[rule.threat.technique]]
+id = "T1595"
+name = "Active Scanning"
+reference = "https://attack.mitre.org/techniques/T1595/"
+
+[[rule.threat.technique.subtechnique]]
+id = "T1595.002"
+name = "Vulnerability Scanning"
+reference = "https://attack.mitre.org/techniques/T1595/002/"
+
+[[rule.threat.technique.subtechnique]]
+id = "T1595.003"
+name = "Wordlist Scanning"
+reference = "https://attack.mitre.org/techniques/T1595/003/"
+
+[rule.threat.tactic]
+id = "TA0043"
+name = "Reconnaissance"
+reference = "https://attack.mitre.org/tactics/TA0043/"