huntrule

Windows AppX Deployment: Uncommon Appx Path Added to Deployment Pipeline

Alerts when an AppX package is queued for processing from uncommon paths or URLs in Windows AppX deployment server events.

FreeReviewedSigma · Medium · v2
Product
windows
Service
appxdeployment-server
Author
Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2023-01-11
Updated
2026-07-31
AnalysisDetection
title: "Windows AppX Deployment: Uncommon Appx Path Added to Deployment Pipeline"
id: 1a850de7-d166-4c84-8800-2587657797ea
status: test
description: This rule flags Windows AppX deployment events (EventID 854) where an appx package appears in the deployment pipeline and its Path matches uncommon or suspicious locations. Attackers may abuse the AppX deployment mechanism to stage and deliver malicious packages from atypical directories rather than expected sources. The detection relies on telemetry from the AppX deployment server event stream and examines the Path field for specific directory and URL patterns indicative of unusual package locations.
references:
  - Internal Research
  - https://www.sentinelone.com/labs/inside-malicious-windows-apps-for-malware-deployment/
  - https://learn.microsoft.com/en-us/windows/win32/appxpkg/troubleshooting
  - https://news.sophos.com/en-us/2021/11/11/bazarloader-call-me-back-attack-abuses-windows-10-apps-mechanism/
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/builtin/appxdeployment_server/win_appxdeployment_server_uncommon_package_locations.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2023-01-11
modified: 2025-12-03
tags:
  - attack.stealth
logsource:
  product: windows
  service: appxdeployment-server
detection:
  selection:
    EventID: 854
  filter_main_generic:
    Path|contains:
      - :/Program%20Files
      - :/Windows/System32/
      - :\Program Files (x86)\
      - :\Program Files\
      - :\Windows\ImmersiveControlPanel\
      - :\Windows\PrintDialog\
      - :\Windows\SystemApps\
      - AppData/Local/Temp/WinGet/Microsoft.Winget.Source
      - x-windowsupdate://
  filter_main_specific:
    Path|contains:
      - https://installer.teams.static.microsoft/
      - https://res.cdn.office.net
      - https://statics.teams.cdn.live.net/
      - https://statics.teams.cdn.office.net/
      - microsoft.com
  filter_optional_onedrive:
    Path|contains: AppData\Local\Microsoft\OneDrive\
  filter_optional_winget:
    Path|contains:
      - AppData/Local/Temp/WinGet/Microsoft.Winget.Source
      - AppData\Local\Temp\WinGet\Microsoft.Winget.Source
  filter_optional_x_windowsupdate:
    Path|contains: x-windowsupdate://
  condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
  - Unknown
level: medium
license: DRL-1.1
related:
  - id: c977cb50-3dff-4a9f-b873-9290f56132f1
    type: derived