Windows Process Creation: Uncommon Child Processes Spawned by DefaultPack.EXE
Alerts when DefaultPack.exe spawns an uncommon child process, indicating potential proxy execution on Windows.
- Product
- windows
- Category
- process_creation
- Author
- frack113 (SigmaHQ), DRL 1.1
- Published
- 2022-12-31
- Updated
- 2026-07-31
ATT&CK techniques
Defense EvasionRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule flags process creation events where DefaultPack.EXE spawns a child process that is uncommon for that binary. Attackers may abuse signed or trusted Windows binaries to proxy execution and reduce the visibility of their real payload. The detection relies on Windows process creation telemetry, matching on the parent process path ending with \DefaultPack.exe.
Reporting behind it
- lolbas-project.github.iohttps://lolbas-project.github.io/lolbas/OtherMSBinaries/DefaultPack/
- echotrail.iohttps://www.echotrail.io/insights/search/defaultpack.exe
- github.comhttps://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_defaultpack_uncommon_child_process.yml
Changelog
v2- v2Candidate ingested via manual entry.2026-07-31
- v1No changelog recorded for this version.2026-07-30
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
title: "Windows Process Creation: Uncommon Child Processes Spawned by DefaultPack.EXE"
id: 25fc16d6-e015-453f-b614-72080b7d99f3
status: test
description: This rule flags process creation events where DefaultPack.EXE spawns a child process that is uncommon for that binary. Attackers may abuse signed or trusted Windows binaries to proxy execution and reduce the visibility of their real payload. The detection relies on Windows process creation telemetry, matching on the parent process path ending with \DefaultPack.exe.
references:
- https://lolbas-project.github.io/lolbas/OtherMSBinaries/DefaultPack/
- https://www.echotrail.io/insights/search/defaultpack.exe
- https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_defaultpack_uncommon_child_process.yml
author: frack113, Huntrule Team
date: 2022-12-31
modified: 2024-04-22
tags:
- attack.stealth
- attack.t1218
- attack.execution
logsource:
category: process_creation
product: windows
detection:
selection:
ParentImage|endswith: \DefaultPack.exe
condition: selection
falsepositives:
- Unknown
level: medium
license: DRL-1.1
related:
- id: b2309017-4235-44fe-b5af-b15363011957
type: derived