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Detect WMI method invocation and WMI-spawned child processes

Siemphony@siemphonymediumT1047verified in lab
Matches T1047 where it lands on the victim rather than on the operator's console: any process whose parent is `WmiPrvSE.exe`, which is what remote WMI execution produces on the target — wmiexec, the COM API and `Invoke-WmiMethod -ComputerName` all arrive that way and carry none of the literals an operator types. The command-line arms cover the local forms and are ANDed token-wise rather than as one contiguous substring, so `wmic process call create` with doubled spaces still matches, and `/node:` is bound to `call` so read-only remote inventory (`wmic /node:HOST os get caption`) stays out of scope — unbound, that one term is the noisiest thing in a managed Windows estate and outnumbers real execution by orders of magnitude. OR-ing `ParentImage` against `CommandLine` is what Wazuh cannot express in a single rule; the parent arm is worth the refusal because it is the only arm that sees the remote case at all. UNVERIFIED AS AUTHORED — derived from MITRE ATT&CK DET0364, 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 (InitiatingProcessFolderPath endswith "\\WmiPrvSE.exe" or (ProcessCommandLine contains "process" and ProcessCommandLine contains "call" and ProcessCommandLine contains "create") or (ProcessCommandLine contains "/node:" and ProcessCommandLine contains "call") or (ProcessCommandLine contains "Win32_Process" and ProcessCommandLine contains "Create") or (ProcessCommandLine contains "Invoke-WmiMethod" or ProcessCommandLine contains "Invoke-CimMethod"))

Splunk · SPL

Run this as a search.

index=* (ParentImage="*\\WmiPrvSE.exe" OR (CommandLine="*process*" AND CommandLine="*call*" AND CommandLine="*create*") OR (CommandLine="*/node:*" AND CommandLine="*call*") OR (CommandLine="*Win32_Process*" AND CommandLine="*Create*") OR (CommandLine="*Invoke-WmiMethod*" OR CommandLine="*Invoke-CimMethod*"))

Elastic · ES|QL

Run this as a search.

FROM logs-*| WHERE (TO_LOWER(process.parent.executable) LIKE "*\\\\wmiprvse.exe" OR (TO_LOWER(process.command_line) LIKE "*process*" AND TO_LOWER(process.command_line) LIKE "*call*" AND TO_LOWER(process.command_line) LIKE "*create*") OR (TO_LOWER(process.command_line) LIKE "*/node:*" AND TO_LOWER(process.command_line) LIKE "*call*") OR (TO_LOWER(process.command_line) LIKE "*win32_process*" AND TO_LOWER(process.command_line) LIKE "*create*") OR (TO_LOWER(process.command_line) LIKE "*invoke-wmimethod*" OR TO_LOWER(process.command_line) LIKE "*invoke-cimmethod*"))

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. -->  <!-- 5 rules: the Sigma condition ORs across different fields,       which one rule cannot express. Any one matching is a hit. -->  <rule id="100000" level="7">    <!-- Set <if_sid> to the decoder/base rule for windows so this only evaluates relevant events. -->    <field name="ParentImage" type="pcre2">(?i)\\WmiPrvSE\.exe$</field>    <description>Detect WMI method invocation and WMI-spawned child processes (1/5)</description>    <mitre>      <id>T1047</id>    </mitre>  </rule>   <rule id="100001" level="7">    <!-- Set <if_sid> to the decoder/base rule for windows so this only evaluates relevant events. -->    <field name="CommandLine" type="pcre2">(?i)(?=.*(?:process))(?=.*(?:call))(?=.*(?:create)).*</field>    <description>Detect WMI method invocation and WMI-spawned child processes (2/5)</description>    <mitre>      <id>T1047</id>    </mitre>  </rule>   <rule id="100002" level="7">    <!-- Set <if_sid> to the decoder/base rule for windows so this only evaluates relevant events. -->    <field name="CommandLine" type="pcre2">(?i)(?=.*(?:/node:))(?=.*(?:call)).*</field>    <description>Detect WMI method invocation and WMI-spawned child processes (3/5)</description>    <mitre>      <id>T1047</id>    </mitre>  </rule>   <rule id="100003" level="7">    <!-- Set <if_sid> to the decoder/base rule for windows so this only evaluates relevant events. -->    <field name="CommandLine" type="pcre2">(?i)(?=.*(?:Win32_Process))(?=.*(?:Create)).*</field>    <description>Detect WMI method invocation and WMI-spawned child processes (4/5)</description>    <mitre>      <id>T1047</id>    </mitre>  </rule>   <rule id="100004" level="7">    <!-- Set <if_sid> to the decoder/base rule for windows so this only evaluates relevant events. -->    <field name="CommandLine" type="pcre2">(?i)(Invoke-WmiMethod|Invoke-CimMethod)</field>    <description>Detect WMI method invocation and WMI-spawned child processes (5/5)</description>    <mitre>      <id>T1047</id>    </mitre>  </rule></group>

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