Detection rules › Splunk

Windows Svchost.exe Parent Process Anomaly

Author
Teoderick Contreras, Splunk
Source
upstream

The following analytic detects an anomaly where an svchost.exe process is spawned by a parent process other than the standard services.exe. In a typical Windows environment, svchost.exe is a system process that hosts Windows service DLLs, and is expected to be a child of services.exe. A process deviation from this hierarchy may indicate suspicious behavior, such as malicious code attempting to masquerade as a legitimate system process or evade detection. It is essential to investigate the parent process and associated behavior for further signs of compromise or unauthorized activity.

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.parent_process_name!="services.exe" Processes.parent_process_path!="C:\\Program Files\\Windows Defender\\MsMpEng.exe" Processes.parent_process_path!="C:\\ProgramData\\Microsoft\\Windows Defender\\Platform\\*\\MsMpEng.exe" Processes.process!="unknown" Processes.process_name="svchost.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

Stage 2: search

search

Stage 3: search

search

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.parent_process_namene
  • "services.exe"
Processes.parent_process_pathne
  • "C:\\Program Files\\Windows Defender\\MsMpEng.exe"
  • "C:\\ProgramData\\Microsoft\\Windows Defender\\Platform\\*\\MsMpEng.exe"
Processes.processne
  • unknown corpus 2 (splunk 2)
Processes.process_nameeq
  • "svchost.exe"