Startup/Logon Script Added to Group Policy Object — Sigma Rule

Rule metadata and linked tags

Author: Elastic, Josh Nickels, Marius Rothenbücher. Source status: test; severity: medium. Source dates: 2024-09-06 / not supplied.

{
  "product": "windows",
  "service": "security",
  "definition": "The advanced audit policy setting \"Object Access > Audit Detailed File Share\" must be configured for Success/Failure"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: aa1fcb559701ae8e1244b65f790ee4ae2905df123c484a14baf99bf9289ef674

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Startup/Logon Script Added to Group Policy Object
id: 123e4e6d-b123-48f8-b261-7214938acaf0
status: test
description: |
    Detects the modification of Group Policy Objects (GPO) to add a startup/logon script to users or computer objects.
references:
    - https://www.elastic.co/guide/en/security/current/startup-logon-script-added-to-group-policy-object.html
author: Elastic, Josh Nickels, Marius Rothenbücher
date: 2024-09-06
tags:
    - attack.persistence
    - attack.privilege-escalation
    - attack.defense-impairment
    - attack.t1484.001
    - attack.t1547
logsource:
    product: windows
    service: security
    definition: 'The advanced audit policy setting "Object Access > Audit Detailed File Share" must be configured for Success/Failure'
detection:
    selection_eventid:
        EventID:
            - 5136
            - 5145
    selection_attributes_main:
        AttributeLDAPDisplayName:
            - 'gPCMachineExtensionNames'
            - 'gPCUserExtensionNames'
        AttributeValue|contains: '42B5FAAE-6536-11D2-AE5A-0000F87571E3'
    selection_attributes_optional:
        AttributeValue|contains:
            - '40B6664F-4972-11D1-A7CA-0000F87571E3'
            - '40B66650-4972-11D1-A7CA-0000F87571E3'
    selection_share:
        ShareName|endswith: '\SYSVOL'
        RelativeTargetName|endswith:
            - '\scripts.ini'
            - '\psscripts.ini'
        AccessList|contains: '%%4417'
    condition: selection_eventid and (all of selection_attributes_* or selection_share)
falsepositives:
    - Legitimate execution by system administrators.
level: medium

Original YAML and metadata in JSON

False positives

• Legitimate execution by system administrators.

Source references

• https://www.elastic.co/guide/en/security/current/startup-logon-script-added-to-group-policy-object.html