Detection rules › Sigma
High risk Active Directory group membership change
Detects scenarios where a suspicious group membership is changed.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Persistence | T1098 Account Manipulation |
Event coverage
| Provider | Event | Title |
|---|---|---|
| Security-Auditing | Event ID 4728 | A member was added to a security-enabled global group. |
| Security-Auditing | Event ID 4756 | A member was added to a security-enabled universal group. |
Rule body yaml
title: High risk Active Directory group membership change
description: Detects scenarios where a suspicious group membership is changed.
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0003-Persistence/T1098.xxx-Account%20manipulation
- https://ss64.com/nt/syntax-groups.html
- https://docs.microsoft.com/en-us/windows/security/identity-protection/access-control/security-identifiers
tags:
- attack.persistence
- attack.t1098
author: mdecrevoisier
status: experimental
logsource:
product: windows
service: security
detection:
selection:
EventID:
- 4728 # security global group member added
- 4756 # universal group member added
#- 4732 # local and domain local group are covered in another rule
TargetSid|startswith: 'S-1-5-21-'
TargetSid|endswith:
- '-512' # Domain Admins (global)
- '-518' # Schema Admins (universal)
- '-519' # Enterprise Admins (universal)
- '-520' # Group Policy Creator Owners (global)
#- '-525' # Protected users (global) > focus only on removal actions, not adding . See dedicated rule
- '-526' # Key Admins (global)
- '-527' # Enterprise Key Admins (universal)
condition: selection
falsepositives:
- Administrator activity
level: high
Stages and Predicates
Stage 0: condition
selectionStage 1: selection
selection:
EventID:
- 4728
- 4756
TargetSid|startswith: 'S-1-5-21-'
TargetSid|endswith:
- '-512'
- '-518'
- '-519'
- '-520'
- '-526'
- '-527'
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.