Detectionmediumtest

Access To Potentially Sensitive Sysvol Files By Uncommon Applications

Detects file access requests to potentially sensitive files hosted on the Windows Sysvol share.

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François HubautCreated Thu Dec 21Updated Mon Jul 29d51694fe-484a-46ac-92d6-969e76d60d10windows
Log Source
Windowsfile_access
ProductWindows← raw: windows
Categoryfile_access← raw: file_access

Definition

Requirements: Microsoft-Windows-Kernel-File ETW provider

Detection Logic
Detection Logic3 selectors
detection:
    selection:
        FileName|startswith: '\\'
        FileName|contains|all:
            - '\sysvol\'
            - '\Policies\'
        FileName|endswith:
            - 'audit.csv'
            - 'Files.xml'
            - 'GptTmpl.inf'
            - 'groups.xml'
            - 'Registry.pol'
            - 'Registry.xml'
            - 'scheduledtasks.xml'
            - 'scripts.ini'
            - 'services.xml'
    filter_main_generic:
        Image|startswith:
            - 'C:\Program Files (x86)\'
            - 'C:\Program Files\'
            - 'C:\Windows\system32\'
            - 'C:\Windows\SysWOW64\'
    filter_main_explorer:
        Image: 'C:\Windows\explorer.exe'
    condition: selection and not 1 of filter_main_*
False Positives
Unknown

False positive likelihood has not been assessed. Additional context may be needed during triage.

Rule Metadata
Rule ID
d51694fe-484a-46ac-92d6-969e76d60d10
Status
test
Level
medium
Type
Detection
Created
Thu Dec 21
Modified
Mon Jul 29
Path
rules/windows/file/file_access/file_access_win_susp_gpo_files.yml
Raw Tags
attack.credential-accessattack.t1552.006
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