Esentutl Volume Shadow Copy Service Keys

Hunt Hypothesis

Detects the volume shadow copy service initialization and processing via esentutl. Registry keys such as HKLM\System\CurrentControlSet\Services\VSS\Diag\VolSnap\Volume are captured.

Detection Rule

Sigma (Original)

title: Esentutl Volume Shadow Copy Service Keys
id: 5aad0995-46ab-41bd-a9ff-724f41114971
status: test
description: Detects the volume shadow copy service initialization and processing via esentutl. Registry keys such as HKLM\\System\\CurrentControlSet\\Services\\VSS\\Diag\\VolSnap\\Volume are captured.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1003.002/T1003.002.md#atomic-test-3---esentutlexe-sam-copy
author: Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research)
date: 2020-10-20
modified: 2022-12-25
tags:
    - attack.credential-access
    - attack.t1003.002
logsource:
    category: registry_event
    product: windows
detection:
    selection:
        TargetObject|contains: 'System\CurrentControlSet\Services\VSS'
        Image|endswith: 'esentutl.exe' # limit esentutl as in references, too many FP to filter
    filter:
        TargetObject|contains: 'System\CurrentControlSet\Services\VSS\Start'
    condition: selection and not filter
falsepositives:
    - Unknown
level: high

KQL (Azure Sentinel)

imRegistry
| where (RegistryKey contains "System\\CurrentControlSet\\Services\\VSS" and ActingProcessName endswith "esentutl.exe") and (not(RegistryKey contains "System\\CurrentControlSet\\Services\\VSS\\Start"))

Required Data Sources

False Positive Guidance

• Unknown

MITRE ATT&CK Context

• Tactic: Credential Access
• Technique: T1003.002 — T1003.002

References

• https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1003.002/T1003.002.md#atomic-test-3---esentutlexe-sam-copy
• SigmaHQ Rule