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Uncommon Child Process Of Appvlp.EXE

Detects uncommon child processes of Appvlp.EXE Appvlp or the Application Virtualization Utility is included with Microsoft Office. Attackers are able to abuse "AppVLP" to execute shell commands. Normally, this binary is used for Application Virtualization, but it can also be abused to circumvent the ASR file path rule folder or to mark a file as a system file.

MITRE ATT&CK

T1218

defense-evasionexecution

Detection Query

selection:
  ParentImage|endswith: \appvlp.exe
filter_main_generic:
  Image|endswith:
    - :\Windows\SysWOW64\rundll32.exe
    - :\Windows\System32\rundll32.exe
filter_optional_office_msoasb:
  Image|contains: :\Program Files\Microsoft Office
  Image|endswith: \msoasb.exe
filter_optional_office_skype:
  Image|contains|all:
    - :\Program Files\Microsoft Office
    - \SkypeSrv\
  Image|endswith: \SKYPESERVER.EXE
filter_optional_office_msouc:
  Image|contains: :\Program Files\Microsoft Office
  Image|endswith: \MSOUC.EXE
condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*

Author

Sreeman

Created

2020-03-13

Data Sources

windowsProcess Creation Events

Platforms

windows

References

https://lolbas-project.github.io/lolbas/OtherMSBinaries/Appvlp/

Tags

attack.t1218attack.defense-evasionattack.execution

Raw Content

title: Uncommon Child Process Of Appvlp.EXE
id: 9c7e131a-0f2c-4ae0-9d43-b04f4e266d43
status: test
description: |
    Detects uncommon child processes of Appvlp.EXE
    Appvlp or the Application Virtualization Utility is included with Microsoft Office. Attackers are able to abuse "AppVLP" to execute shell commands.
    Normally, this binary is used for Application Virtualization, but it can also be abused to circumvent the ASR file path rule folder
    or to mark a file as a system file.
references:
    - https://lolbas-project.github.io/lolbas/OtherMSBinaries/Appvlp/
author: Sreeman
date: 2020-03-13
modified: 2023-11-09
tags:
    - attack.t1218
    - attack.defense-evasion
    - attack.execution
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        ParentImage|endswith: '\appvlp.exe'
    # Note: Filters based on data from EchoTrail: https://www.echotrail.io/insights/search/appvlp.exe/
    filter_main_generic:
        Image|endswith:
            - ':\Windows\SysWOW64\rundll32.exe'
            - ':\Windows\System32\rundll32.exe'
    filter_optional_office_msoasb:
        Image|contains: ':\Program Files\Microsoft Office'
        Image|endswith: '\msoasb.exe'
    filter_optional_office_skype:
        Image|contains|all:
            - ':\Program Files\Microsoft Office'
            - '\SkypeSrv\'
        Image|endswith: '\SKYPESERVER.EXE'
    filter_optional_office_msouc:
        Image|contains: ':\Program Files\Microsoft Office'
        Image|endswith: '\MSOUC.EXE'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
    - Unknown
level: medium