Detection rules › Splunk

Windows PowerView AD Access Control List Enumeration

Author
Mauricio Velazco, Splunk
Source
upstream

The following analytic detects the execution of PowerView PowerShell cmdlets Get-ObjectAcl or Get-DomainObjectAcl, which are used to enumerate Access Control List (ACL) permissions for Active Directory objects. It leverages Event ID 4104 from PowerShell Script Block Logging to identify this activity. This behavior is significant as it may indicate an attempt to discover weak permissions in Active Directory, potentially leading to privilege escalation. If confirmed malicious, attackers could exploit these permissions to gain unauthorized access or escalate their privileges within the network.

MITRE ATT&CK coverage

TacticTechniques
Initial AccessT1078.002 Valid Accounts: Domain Accounts
PersistenceT1078.002 Valid Accounts: Domain Accounts
Privilege EscalationT1078.002 Valid Accounts: Domain Accounts
Defense EvasionT1078.002 Valid Accounts: Domain Accounts
DiscoveryT1069 Permission Groups Discovery

Event coverage

ProviderEvent IDTitle
PowerShell4104Creating Scriptblock text (MessageNumber of MessageTotal).

Stages and Predicates

Stage 1: search

search (ScriptBlockText="*Get-DomainObjectAcl*" OR ScriptBlockText="*get-objectacl*") EventCode=4104

Stage 2: fillnull

fillnull

Stage 3: stats

stats BY dest, signature, signature_id, user_id, vendor_product, EventID, Guid, Opcode, Name, Path, ProcessID, ScriptBlockId, ScriptBlockText

Stage 4: search

search

Stage 5: search

search

Stage 6: search

search `macro`

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.

FieldKindValues
EventCodeeq
  • 4104 corpus 108 (splunk 108)
ScriptBlockTexteq
  • *Get-DomainObjectAcl*
  • *get-objectacl*

Neighbors

Broader alternatives (more inclusive than this rule)

These rules match a superset of what this rule catches. They cover the same events plus more. Use them if you want wider coverage and can absorb more false positives.