Windows Software Discovery Via PowerShell
Description
Detects the use of PowerShell based registry queries to pull installed software information from the Uninstall key. This will give an attacker version information on installed software which could be used to identify further vulnerabilities. False positives are unlikely as this is an unusual key to query with PowerShell.
Query · spl
`powershell`
EventID="4104"
ScriptBlockText="*Get-ItemProperty *"
ScriptBlockText="*Windows\\CurrentVersion\\Uninstall*"
| fillnull
| stats count min(_time) as firstTime
max(_time) as lastTime
by Computer EventID ScriptBlockText signature signature_id user_id vendor_product Guid
Opcode Name Path ProcessID ScriptBlockId
| rename Computer as dest
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_software_discovery_via_powershell_filter`
Implementation guide
The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the Processes node of the Endpoint data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.
Known false positives
- Legitimate system administrators or security tools may query the Uninstall key via PowerShell for software inventory or compliance checks. Filter as needed to allow authorized management scripts.
Analyst notes
Known false positives: Legitimate system administrators or security tools may query the Uninstall key via PowerShell for software inventory or compliance checks. Filter as needed to allow authorized management scripts.