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Group Policy enumeration via gpresult or GPO cmdlets

Siemphony@siemphonylowT1615unverified
Matches the command line of a process that names a Group Policy enumeration tool. AN0152 names two of them itself — gpresult and the PowerView function Get-DomainGPO; the substring match on Get-DomainGPO also covers Get-DomainGPOLocalGroup, the third name in the analytic. The remaining values are added here, not sourced from MITRE: the RSAT GroupPolicy cmdlets Get-GPO and Get-GPResultantSetOfPolicy, and Get-NetGPO, the PowerView v2 name for the same enumeration function. It is a single CommandLine list rather than an Image list plus a keyword search, so the invocation is caught whether the binary is launched directly or wrapped in powershell.exe -Command, and so every backend renders one field. AN0152's other two legs are not written here: its Security 4661 leg needs a SACL on the domain's groupPolicyContainer objects and an object-type GUID match that this brief supplies no field names for, and its PowerShell 4103/4104 leg is a different logsource. Two limitations follow from matching a command line and belong in the reader's expectations rather than in the false positives — a cmdlet typed at an interactive prompt or called from inside a .ps1 never reaches a command line at all, and a base64 -EncodedCommand hides the name. The telemetry is Sysmon EventID 1 per the brief; sourced from Security 4688 instead it needs *Audit Process Creation* plus the separate *Include command line in process creation events* policy, neither on by default. UNVERIFIED AS AUTHORED — derived from MITRE ATT&CK DET0055, not hand-written and not tested by its author. Any lab result is on this rule's own page.Full description

The detection

The 4 SIEM queries below are previews produced by Siemphony’s own translator, not pySigma, and none has been executed against a real backend — review before you deploy.

detection.yml

Sentinel · KQL

Run this as a search.

DeviceProcessEvents| where (ProcessCommandLine contains "gpresult" or ProcessCommandLine contains "Get-GPO" or ProcessCommandLine contains "Get-GPResultantSetOfPolicy" or ProcessCommandLine contains "Get-DomainGPO" or ProcessCommandLine contains "Get-NetGPO")

Splunk · SPL

Run this as a search.

index=* (CommandLine="*gpresult*" OR CommandLine="*Get-GPO*" OR CommandLine="*Get-GPResultantSetOfPolicy*" OR CommandLine="*Get-DomainGPO*" OR CommandLine="*Get-NetGPO*")

Elastic · ES|QL

Run this as a search.

FROM logs-*| WHERE (TO_LOWER(process.command_line) LIKE "*gpresult*" OR TO_LOWER(process.command_line) LIKE "*get-gpo*" OR TO_LOWER(process.command_line) LIKE "*get-gpresultantsetofpolicy*" OR TO_LOWER(process.command_line) LIKE "*get-domaingpo*" OR TO_LOWER(process.command_line) LIKE "*get-netgpo*")

Wazuh · XML rule

Deploy to your manager — this is a rule, not a search.

<group name="sigma,windows,process_creation,">  <!-- Rule ids must be unique on your manager; 100000+ is the user range. -->  <rule id="100000" level="5">    <!-- Set <if_sid> to the decoder/base rule for windows so this only evaluates relevant events. -->    <field name="CommandLine" type="pcre2">(?i)(gpresult|Get-GPO|Get-GPResultantSetOfPolicy|Get-DomainGPO|Get-NetGPO)</field>    <description>Group Policy enumeration via gpresult or GPO cmdlets</description>    <mitre>      <id>T1615</id>    </mitre>  </rule></group>

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