Potential WMI Lateral Movement WmiPrvSE Spawned PowerShell

Severity: medium
Author: Markus Neis @Karneades
Source: upstream

Detects Powershell as a child of the WmiPrvSE process. Which could be a sign of lateral movement via WMI.

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1047` Windows Management Instrumentation, `T1059.001` Command and Scripting Interpreter: PowerShell

Event coverage

Provider	Event ID	Title
Sysmon	1	Process creation

Stages and Predicates

Stage 1: `all of selection_parent`

ParentImage|endswith: '\WmiPrvSE.exe'

Stage 2: `all of selection_img`

or:
Image|endswith: '\powershell.exe'
Image|endswith: '\pwsh.exe'
OriginalFileName: PowerShell.EXE
OriginalFileName: pwsh.dll

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.

Field	Kind	Values
`Image`	ends_with	`\powershell.exe` corpus 143 (sigma 143) `\pwsh.exe` corpus 140 (sigma 140)
`OriginalFileName`	eq	`PowerShell.EXE` corpus 64 (sigma 60, splunk 4) `pwsh.dll` corpus 72 (sigma 68, splunk 4)
`ParentImage`	ends_with	`\WmiPrvSE.exe` corpus 3 (sigma 3)