sigma-rules/rules_building_block/discovery_win_network_connections.toml

[metadata]
bypass_bbr_timing = true
creation_date = "2023/07/14"
integration = ["endpoint"]
maturity = "production"
updated_date = "2026/03/24"

[rule]
author = ["Elastic"]
building_block_type = "default"
description = """
This rule identifies the execution of commands that can be used to enumerate network connections. Adversaries may
attempt to get a listing of network connections to or from a compromised system to identify targets within an
environment.
"""
from = "now-9m"
index = ["logs-endpoint.events.process-*"]
language = "eql"
license = "Elastic License v2"
name = "Windows System Network Connections Discovery"
risk_score = 21
rule_id = "c4e9ed3e-55a2-4309-a012-bc3c78dad10a"
severity = "low"
tags = [
    "Domain: Endpoint",
    "OS: Windows",
    "Use Case: Threat Detection",
    "Tactic: Discovery",
    "Rule Type: BBR",
    "Data Source: Elastic Defend",
]
timestamp_override = "event.ingested"
type = "eql"

query = '''
process where event.type == "start" and
(
  process.name : "netstat.exe" or
  (
   (
    (process.name : "net.exe" or process.pe.original_file_name == "net.exe") or
    (
     (process.name : "net1.exe" or process.pe.original_file_name == "net1.exe") and
     not process.parent.name : "net.exe"
    )
   ) and process.args : ("use", "user", "session", "config") and not process.args: ("/persistent:*", "/delete", "\\\\*")
  ) or
  (process.name : "nbtstat.exe" and process.args : "-s*")
) and not user.id : "S-1-5-18"
'''


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

[[rule.threat.technique]]
id = "T1016"
name = "System Network Configuration Discovery"
reference = "https://attack.mitre.org/techniques/T1016/"

[[rule.threat.technique]]
id = "T1049"
name = "System Network Connections Discovery"
reference = "https://attack.mitre.org/techniques/T1049/"

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

[[rule.threat.technique]]
id = "T1087"
name = "Account Discovery"
reference = "https://attack.mitre.org/techniques/T1087/"

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