Windows MSIExec Spawn WinDBG
Description
The following analytic identifies the unusual behavior of MSIExec spawning WinDBG. It detects this activity by analyzing endpoint telemetry data, specifically looking for instances where 'msiexec.exe' is the parent process of 'windbg.exe'. This behavior is significant as it may indicate an attempt to debug or tamper with system processes, which is uncommon in typical user activity and could signify malicious intent. If confirmed malicious, this activity could allow an attacker to manipulate or inspect running processes, potentially leading to privilege escalation or persistence within the environment.
Query · spl
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Processes
WHERE Processes.parent_process_name=msiexec.exe Processes.process_name=windbg.exe
BY Processes.action Processes.dest Processes.original_file_name
Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
Processes.process Processes.process_exec Processes.process_guid
Processes.process_hash Processes.process_id Processes.process_integrity_level
Processes.process_name Processes.process_path Processes.user
Processes.user_id Processes.vendor_product
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_msiexec_spawn_windbg_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
- False positives will only be present if the MSIExec process legitimately spawns WinDBG. Filter as needed.
Analyst notes
Known false positives: False positives will only be present if the MSIExec process legitimately spawns WinDBG. Filter as needed.