Detection rules › Sigma
Active Directory User Backdoors
Detects scenarios where one can control another users or computers account without having to use their credentials.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Persistence | |
| Privilege Escalation |
Telemetry coverage
Rule body
title: Active Directory User Backdoors
id: 300bac00-e041-4ee2-9c36-e262656a6ecc
status: test
description: Detects scenarios where one can control another users or computers account without having to use their credentials.
references:
- https://msdn.microsoft.com/en-us/library/cc220234.aspx
- https://adsecurity.org/?p=3466
- https://blog.harmj0y.net/redteaming/another-word-on-delegation/
author: '@neu5ron'
date: 2017-04-13
modified: 2024-02-26
tags:
- attack.privilege-escalation
- attack.t1098
- attack.persistence
logsource:
product: windows
service: security
definition: 'Requirements: Audit Policy : Account Management > Audit User Account Management, Group Policy : Computer Configuration\Windows Settings\Security Settings\Advanced Audit Policy Configuration\Audit Policies\Account Management\Audit User Account Management, DS Access > Audit Directory Service Changes, Group Policy : Computer Configuration\Windows Settings\Security Settings\Advanced Audit Policy Configuration\Audit Policies\DS Access\Audit Directory Service Changes'
detection:
selection1:
EventID: 4738
filter_empty:
AllowedToDelegateTo:
- ''
- '-'
filter_null:
AllowedToDelegateTo: null
selection_5136_1:
EventID: 5136
AttributeLDAPDisplayName: 'msDS-AllowedToDelegateTo'
selection_5136_2:
EventID: 5136
ObjectClass: 'user'
AttributeLDAPDisplayName: 'servicePrincipalName'
selection_5136_3:
EventID: 5136
AttributeLDAPDisplayName: 'msDS-AllowedToActOnBehalfOfOtherIdentity'
condition: (selection1 and not 1 of filter_*) or 1 of selection_5136_*
falsepositives:
- Unknown
level: high
Stages and Predicates
Stage 0: condition
(selection1 and not 1 of filter_*) or 1 of selection_5136_*Stage 1: selection1
selection1:
EventID: 4738
Stage 2: not filter_*
filter_empty:
AllowedToDelegateTo:
- ''
- '-'
filter_null:
AllowedToDelegateTo: null
Stage 3: selection_5136_1
selection_5136_1:
EventID: 5136
AttributeLDAPDisplayName: 'msDS-AllowedToDelegateTo'
Stage 4: selection_5136_2
selection_5136_2:
EventID: 5136
ObjectClass: 'user'
AttributeLDAPDisplayName: 'servicePrincipalName'
Stage 5: selection_5136_3
selection_5136_3:
EventID: 5136
AttributeLDAPDisplayName: 'msDS-AllowedToActOnBehalfOfOtherIdentity'
Exclusions
The rule actively suppresses these predicates.
| Field | Kind | Excluded values | Search |
|---|---|---|---|
AllowedToDelegateTo | eq | - | excludes:AllowedToDelegateTo field:"AllowedToDelegateTo" value:"-" |
AllowedToDelegateTo | is_null | excludes:AllowedToDelegateTo |
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
AttributeLDAPDisplayName | eq |
| field:"AttributeLDAPDisplayName" kind:eq |
ObjectClass | eq |
| field:"ObjectClass" kind:eq value:"user" |