Windows Image Load: coregen.exe Potential DLL Sideloading

Identifies potential DLL sideloading when coregen.exe loads DLLs outside expected system and Silverlight locations.

FreeReviewedSigma · Medium · v2

Product: windows
Category: image_load
Author: frack113 (SigmaHQ), DRL 1.1
Published: 2022-12-31
Updated: 2026-07-31

ATT&CK techniques

Priv Esc → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
- T1055Process Injection
Defense Evasion
- T1055Process Injection
- T1218System Binary Proxy Execution
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

Identifies execution of coregen.exe followed by DLL image loads, where the loaded DLL path is not one of the expected system or Microsoft Silverlight directories. Attackers can abuse coregen.exe to load attacker-supplied or non-standard DLLs, supporting stealthy execution and potential privilege escalation. The rule relies on image load telemetry that includes the loading process path and the loaded DLL path.

Reporting behind it

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Windows Image Load: coregen.exe Potential DLL Sideloading

Pivot detection · T1055 · 9 related

Changelog

v2
Candidate ingested via manual entry.2026-07-31
v1
No 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.

windows-dll-sideloading-via-coregen-exe-0fa66f66

title: "Windows Image Load: coregen.exe Potential DLL Sideloading"
id: 2124fed4-a776-4cc8-a296-7e1cd8ee3ae7
status: test
description: Identifies execution of coregen.exe followed by DLL image loads, where the loaded DLL path is not one of the expected system or Microsoft Silverlight directories. Attackers can abuse coregen.exe to load attacker-supplied or non-standard DLLs, supporting stealthy execution and potential privilege escalation. The rule relies on image load telemetry that includes the loading process path and the loaded DLL path.
references:
  - https://lolbas-project.github.io/lolbas/OtherMSBinaries/Coregen/
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/image_load/image_load_side_load_coregen.yml
author: frack113, Huntrule Team
date: 2022-12-31
tags:
  - attack.privilege-escalation
  - attack.stealth
  - attack.t1218
  - attack.t1055
logsource:
  category: image_load
  product: windows
detection:
  selection:
    Image|endswith: \coregen.exe
  filter_main_legit_paths:
    ImageLoaded|startswith:
      - C:\Program Files (x86)\Microsoft Silverlight\
      - C:\Program Files\Microsoft Silverlight\
      - C:\Windows\System32\
      - C:\Windows\SysWOW64\
  condition: selection and not 1 of filter_main_*
falsepositives:
  - Unknown
level: medium
license: DRL-1.1
related:
  - id: 0fa66f66-e3f6-4a9c-93f8-4f2610b00171
    type: derived

Convert

This rule as a query you can run. Uses no unlock credit.

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