Detection rules › Splunk

Windows Unusual SysWOW64 Process Run System32 Executable

Author
Teoderick Contreras, Splunk
Source
upstream

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.

MITRE ATT&CK coverage

TacticTechniques
Defense EvasionT1036.009 Masquerading: Break Process Trees

Event coverage

ProviderEvent IDTitle
Sysmon1Process creation
Security-Auditing4688A new process has been created.

Stages and Predicates

Stage 1: tstats

tstats WHERE Processes.process="*windows\\system32\\*" Processes.process_path="*\\Windows\\SysWOW64\\*" 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

Stage 2: search

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Stage 3: search

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Stage 4: search

search

Stage 5: search

search `macro`

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.

FieldKindValues
Processes.processeq
  • "*windows\\system32\\*"
Processes.process_patheq
  • "*\\Windows\\SysWOW64\\*"