Windows: Alert on Uncommon Child Process Executed from Appvlp.exe

Alerts on unusual child processes created by Appvlp.EXE on Windows, indicating potential command execution abuse.

FreeReviewedSigma · Medium · v2
Product
windows
Category
process_creation
Author
Sreeman (SigmaHQ), DRL 1.1
Published
2020-03-13
Updated
2026-07-31
title: "Windows: Alert on Uncommon Child Process Executed from Appvlp.exe"
id: 964f815a-44b2-41f6-811c-4ad6b6968243
status: test
description: This rule flags process creations where the parent process is Appvlp.exe, but the spawned child process is uncommon relative to common rundll32 usage. Appvlp is typically associated with Microsoft Application Virtualization, and attackers may abuse it to launch command execution or other actions while blending into legitimate Office-related activity. The detection relies on Windows process creation telemetry, specifically the parent image path ending with \appvlp.exe and the child process image path matching or not matching known benign patterns.
references:
  - https://lolbas-project.github.io/lolbas/OtherMSBinaries/Appvlp/
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_appvlp_uncommon_child_process.yml
author: Sreeman, Huntrule Team
date: 2020-03-13
modified: 2023-11-09
tags:
  - attack.stealth
  - attack.t1218
  - attack.execution
logsource:
  category: process_creation
  product: windows
detection:
  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_*
falsepositives:
  - Unknown
level: medium
license: DRL-1.1
related:
  - id: 9c7e131a-0f2c-4ae0-9d43-b04f4e266d43
    type: derived