Detectionmediumtest

ADSI-Cache File Creation By Uncommon Tool

Detects the creation of an "Active Directory Schema Cache File" (.sch) file by an uncommon tool.

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xknow, Tim SheltonCreated Sun Mar 24Updated Wed Oct 1875bf09fa-1dd7-4d18-9af9-dd9e492562ebwindows

Log Source

WindowsFile Event

ProductWindows← raw: windows

CategoryFile Event← raw: file_event

Events for file system activity including creation, modification, and deletion.

Detection Logic

detection:
    selection:
        TargetFilename|contains: '\Local\Microsoft\Windows\SchCache\'
        TargetFilename|endswith: '.sch'
    filter_main_generic:
        - Image|endswith:
              - ':\Program Files\Cylance\Desktop\CylanceSvc.exe'
              - ':\Windows\CCM\CcmExec.exe'
              - ':\windows\system32\dllhost.exe'
              - ':\Windows\system32\dsac.exe'
              - ':\Windows\system32\efsui.exe'
              - ':\windows\system32\mmc.exe'
              - ':\windows\system32\svchost.exe'
              - ':\Windows\System32\wbem\WmiPrvSE.exe'
              - ':\windows\system32\WindowsPowerShell\v1.0\powershell.exe'
        - Image|contains:
              - ':\Windows\ccmsetup\autoupgrade\ccmsetup' # C:\Windows\ccmsetup\autoupgrade\ccmsetup.TMC00002.40.exe
              - ':\Program Files\SentinelOne\Sentinel Agent' # C:\Program Files\SentinelOne\Sentinel Agent 21.7.7.40005\SentinelAgent.exe
    filter_main_office:
        Image|contains|all:
            - ':\Program Files\'
            - '\Microsoft Office'
        Image|endswith: '\OUTLOOK.EXE'
    filter_optional_ldapwhoami:
        Image|endswith: '\LANDesk\LDCLient\ldapwhoami.exe'
    filter_optional_citrix:
        # Example:
        #   TargetFilename=C:\Windows\ServiceProfiles\NetworkService\AppData\Local\Microsoft\Windows\SchCache\REDACTED.com.sch
        Image|endswith: ':\Program Files\Citrix\Receiver StoreFront\Services\DefaultDomainServices\Citrix.DeliveryServices.DomainServices.ServiceHost.exe'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*