Suspicious Volume Shadow Copy Vssapi.dll Load

 1title: Suspicious Volume Shadow Copy Vssapi.dll Load
 2id: 37774c23-25a1-4adb-bb6d-8bb9fd59c0f8
 3related:
 4    - id: 333cdbe8-27bb-4246-bf82-b41a0dca4b70 # vss_ps.dll
 5      type: similar
 6    - id: 48bfd177-7cf2-412b-ad77-baf923489e82 # vsstrace.dll
 7      type: similar
 8status: test
 9description: Detects the image load of VSS DLL by uncommon executables
10references:
11    - https://github.com/ORCx41/DeleteShadowCopies
12author: frack113
13date: 2022/10/31
14modified: 2023/05/03
15tags:
16    - attack.defense_evasion
17    - attack.impact
18    - attack.t1490
19logsource:
20    category: image_load
21    product: windows
22detection:
23    selection:
24        ImageLoaded|endswith: '\vssapi.dll'
25    filter_windows:
26        - Image:
27              - 'C:\Windows\explorer.exe'
28              - 'C:\Windows\ImmersiveControlPanel\SystemSettings.exe'
29        - Image|startswith:
30              - 'C:\Windows\System32\'
31              - 'C:\Windows\SysWOW64\'
32              - 'C:\Windows\Temp\{' # Installers
33              - 'C:\Windows\WinSxS\'
34    filter_program_files:
35        # When using this rule in your environment replace the "Program Files" folder by the exact applications you know use this. Examples would be software such as backup solutions
36        Image|startswith:
37            - 'C:\Program Files\'
38            - 'C:\Program Files (x86)\'
39    filter_programdata_packagecache:
40        # The following filter is required because of many FPs cause by:
41        #   C:\ProgramData\Package Cache\{10c6cfdc-27af-43fe-bbd3-bd20aae88451}\dotnet-sdk-3.1.425-win-x64.exe
42        #   C:\ProgramData\Package Cache\{b9cfa33e-ace4-49f4-8bb4-82ded940990a}\windowsdesktop-runtime-6.0.11-win-x86.exe
43        #   C:\ProgramData\Package Cache\{50264ff2-ad47-4569-abc4-1c350f285fb9}\aspnetcore-runtime-6.0.11-win-x86.exe
44        #   C:\ProgramData\Package Cache\{2dcef8c3-1563-4149-a6ec-5b6c98500d7d}\dotnet-sdk-6.0.306-win-x64.exe
45        #   etc.
46        Image|startswith: 'C:\ProgramData\Package Cache\'
47    condition: selection and not 1 of filter_*
48falsepositives:
49    - Unknown
50level: high