Detection rules › Elastic

Linux System Information Discovery

Status
production
Kind
building block (feeds higher-level correlation rules; not a standalone alert)
Severity
low
Time window
119m
Group by
host.id, process.command_line, process.parent.executable
Author
Elastic
Source
github.com/elastic/detection-rules

This rule identifies Linux system information discovery activity via built-in commands that read common system files. Adversaries may use these commands to gather information about the operating system, installed services, and hardware configuration to aid in further exploration and exploitation of the system.

MITRE ATT&CK coverage

TacticTechniques
DiscoveryT1082 System Information Discovery

Rule body elastic

[metadata]
creation_date = "2023/07/10"
integration = ["endpoint", "sentinel_one_cloud_funnel"]
maturity = "production"
updated_date = "2026/03/02"

[rule]
author = ["Elastic"]
building_block_type = "default"
description = """
This rule identifies Linux system information discovery activity via built-in commands that read common
system files. Adversaries may use these commands to gather information about the operating system, installed
services, and hardware configuration to aid in further exploration and exploitation of the system.
"""
from = "now-119m"
index = ["logs-endpoint.events.*", "endgame-*", "logs-sentinel_one_cloud_funnel.*",]
interval = "60m"
language = "kuery"
license = "Elastic License v2"
name = "Linux System Information Discovery"
risk_score = 21
rule_id = "b81bd314-db5b-4d97-82e8-88e3e5fc9de5"
severity = "low"
tags = [
  "Domain: Endpoint",
  "OS: Linux",
  "Use Case: Threat Detection",
  "Tactic: Discovery",
  "Rule Type: BBR",
  "Data Source: Elastic Defend",
  "Data Source: Elastic Endgame",
  "Data Source: SentinelOne",

]
timestamp_override = "event.ingested"
type = "new_terms"
query = '''
event.category:process and host.os.type:linux and event.type:start and event.action:(exec or exec_event or start) and
process.name:("cat" or "more" or "less" or "nano" or "vi" or "vim" or "vim.basic" or "emacs") and
process.args:(
  "/etc/issue" or "/etc/os-release" or "/proc/version" or "/etc/profile" or "/proc/cpuinfo" or "/etc/services" or
  "/etc/lsb-release" or "/etc/redhat-release" or "/etc/debian_version" or "/etc/hostname"
) and
not process.parent.executable:("/usr/local/jamf/bin/jamf" or "/etc/cp/watchdog/cp-nano-watchdog")
'''

[[rule.threat]]
framework = "MITRE ATT&CK"

[[rule.threat.technique]]
id = "T1082"
name = "System Information Discovery"
reference = "https://attack.mitre.org/techniques/T1082/"

[rule.threat.tactic]
id = "TA0007"
name = "Discovery"
reference = "https://attack.mitre.org/tactics/TA0007/"

[rule.new_terms]
field = "new_terms_fields"
value = ["process.parent.executable", "process.command_line", "host.id"]

[[rule.new_terms.history_window_start]]
field = "history_window_start"
value = "now-5d"

Stages and Predicates

Stage 1: new_terms

event.category:process and host.os.type:linux and event.type:start and event.action:(exec or exec_event or start) and
process.name:("cat" or "more" or "less" or "nano" or "vi" or "vim" or "vim.basic" or "emacs") and
process.args:(
  "/etc/issue" or "/etc/os-release" or "/proc/version" or "/etc/profile" or "/proc/cpuinfo" or "/etc/services" or
  "/etc/lsb-release" or "/etc/redhat-release" or "/etc/debian_version" or "/etc/hostname"
) and
not process.parent.executable:("/usr/local/jamf/bin/jamf" or "/etc/cp/watchdog/cp-nano-watchdog")
New terms
process.parent.executable, process.command_line, host.id
History since
now-5d

Exclusions

Top-level NOT(...) conjuncts: predicates this rule actively suppresses.

FieldKindExcluded values
process.parent.executablein/etc/cp/watchdog/cp-nano-watchdog, /usr/local/jamf/bin/jamf

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
event.actionin
  • exec
  • exec_event
  • start
event.categoryeq
  • process
event.typeeq
  • start
process.argsin
  • /etc/debian_version
  • /etc/hostname
  • /etc/issue
  • /etc/lsb-release
  • /etc/os-release
  • /etc/profile
  • /etc/redhat-release
  • /etc/services
  • /proc/cpuinfo
  • /proc/version
process.namein
  • cat
  • emacs
  • less
  • more
  • nano
  • vi
  • vim
  • vim.basic