[metadata]
creation_date = "2020/12/15"
integration = ["endpoint", "windows"]
maturity = "production"
updated_date = "2024/05/21"

[rule]
author = ["Elastic"]
description = """
Identifies the PowerShell process loading the Task Scheduler COM DLL followed by an outbound RPC network connection
within a short time period. This may indicate lateral movement or remote discovery via scheduled tasks.
"""
false_positives = ["Legitimate scheduled tasks may be created during installation of new software."]
from = "now-9m"
index = [
    "winlogbeat-*",
    "logs-endpoint.events.library-*",
    "logs-endpoint.events.network-*",
    "logs-windows.sysmon_operational-*",
]
language = "eql"
license = "Elastic License v2"
name = "Outbound Scheduled Task Activity via PowerShell"
references = [
    "https://www.volexity.com/blog/2020/12/14/dark-halo-leverages-solarwinds-compromise-to-breach-organizations/",
]
risk_score = 47
rule_id = "5cd55388-a19c-47c7-8ec4-f41656c2fded"
severity = "medium"
tags = [
    "Domain: Endpoint",
    "OS: Windows",
    "Use Case: Threat Detection",
    "Tactic: Execution",
    "Data Source: Elastic Defend",
    "Data Source: Sysmon",
]
type = "eql"

query = '''
sequence by host.id, process.entity_id with maxspan = 5s
 [any where host.os.type == "windows" and (event.category == "library" or (event.category == "process" and event.action : "Image loaded*")) and
  (?dll.name : "taskschd.dll" or file.name : "taskschd.dll") and process.name : ("powershell.exe", "pwsh.exe", "powershell_ise.exe")]
 [network where host.os.type == "windows" and process.name : ("powershell.exe", "pwsh.exe", "powershell_ise.exe") and destination.port == 135 and not destination.address in ("127.0.0.1", "::1")]
'''


[[rule.threat]]
framework = "MITRE ATT&CK"
[[rule.threat.technique]]
id = "T1053"
name = "Scheduled Task/Job"
reference = "https://attack.mitre.org/techniques/T1053/"
[[rule.threat.technique.subtechnique]]
id = "T1053.005"
name = "Scheduled Task"
reference = "https://attack.mitre.org/techniques/T1053/005/"


[[rule.threat.technique]]
id = "T1059"
name = "Command and Scripting Interpreter"
reference = "https://attack.mitre.org/techniques/T1059/"
[[rule.threat.technique.subtechnique]]
id = "T1059.001"
name = "PowerShell"
reference = "https://attack.mitre.org/techniques/T1059/001/"



[rule.threat.tactic]
id = "TA0002"
name = "Execution"
reference = "https://attack.mitre.org/tactics/TA0002/"