ID | Technique | Tactic |
---|---|---|
T1036.009 | Break Process Trees | Defense Evasion |
Detection: Windows Unusual SysWOW64 Process Run System32 Executable
Description
The following analytic detects an unusual process execution pattern where a process running from C:\Windows\SysWOW64\ attempts to execute a binary from C:\Windows\System32. In a typical Windows environment, 32-bit processes under SysWOW64 should primarily interact with 32-bit binaries within the same directory. However, an execution flow where a 32-bit process spawns a 64-bit binary from System32 can indicate potential process injection, privilege escalation, evasion techniques, or unauthorized execution hijacking.
Search
1
2| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process_path = "*\\Windows\\SysWOW64\\*" AND Processes.process = "*windows\\system32\\*" by Processes.parent_process_name Processes.process_path Processes.process Processes.original_file_name Processes.dest Processes.user
3| `drop_dm_object_name(Processes)`
4| `security_content_ctime(firstTime)`
5| `security_content_ctime(lastTime)`
6| `windows_unusual_syswow64_process_run_system32_executable_filter`
Data Source
Name | Platform | Sourcetype | Source |
---|---|---|---|
Sysmon EventID 1 | 'xmlwineventlog' |
'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational' |
|
Windows Event Log Security 4688 | 'xmlwineventlog' |
'XmlWinEventLog:Security' |
Macros Used
Name | Value |
---|---|
security_content_ctime | convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$) |
windows_unusual_syswow64_process_run_system32_executable_filter | search * |
windows_unusual_syswow64_process_run_system32_executable_filter
is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Annotations
Default Configuration
This detection is configured by default in Splunk Enterprise Security to run with the following settings:
Setting | Value |
---|---|
Disabled | true |
Cron Schedule | 0 * * * * |
Earliest Time | -70m@m |
Latest Time | -10m@m |
Schedule Window | auto |
Creates Risk Event | True |
Implementation
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
some legitimate system processes, software updaters, or compatibility tools may trigger this behavior, occurrences involving unknown, unsigned, or unusual parent processes should be investigated for potential malware activity, persistence mechanisms, or execution flow hijacking.
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message:
a 32 bit process execute 64 bit executable on [$dest$].
Risk Object | Risk Object Type | Risk Score | Threat Objects |
---|---|---|---|
dest | system | 40 | process_path |
References
Detection Testing
Test Type | Status | Dataset | Source | Sourcetype |
---|---|---|---|---|
Validation | ✅ Passing | N/A | N/A | N/A |
Unit | ✅ Passing | Dataset | XmlWinEventLog:Microsoft-Windows-Sysmon/Operational |
XmlWinEventLog |
Integration | ✅ Passing | Dataset | XmlWinEventLog:Microsoft-Windows-Sysmon/Operational |
XmlWinEventLog |
Replay any dataset to Splunk Enterprise by using our replay.py
tool or the UI.
Alternatively you can replay a dataset into a Splunk Attack Range
Source: GitHub | Version: 1