Windows Image Load: Unsigned dbghelp.dll/dbgcore.dll Loaded by Suspicious Process

Alerts on unsigned loading of dbghelp.dll/dbgcore.dll, often associated with memory dump creation and credential-access workflows.

FreeReviewedSigma · High · v2
Product
windows
Category
image_load
Author
Perez Diego (@darkquassar), oscd.community, Ecco (SigmaHQ), DRL 1.1
Published
2019-10-27
Updated
2026-07-31
title: "Windows Image Load: Unsigned dbghelp.dll/dbgcore.dll Loaded by Suspicious Process"
id: f8894dff-6084-4c05-9080-b524186276ce
related:
  - id: 0e277796-5f23-4e49-a490-483131d4f6e1
    type: similar
  - id: bdc64095-d59a-42a2-8588-71fd9c9d9abc
    type: derived
status: test
description: This rule flags Windows processes that load dbghelp.dll or dbgcore.dll when the loaded DLL is unsigned. These libraries can be used to generate memory dumps via MiniDumpWriteDump, which attackers may use to access sensitive process memory such as credentials. It relies on image load telemetry (DLL path ending with dbghelp.dll/dbgcore.dll) and the signed status of the loaded module.
references:
  - https://learn.microsoft.com/en-us/windows/win32/api/minidumpapiset/nf-minidumpapiset-minidumpwritedump
  - https://www.pinvoke.net/default.aspx/dbghelp/MiniDumpWriteDump.html
  - https://medium.com/@fsx30/bypass-edrs-memory-protection-introduction-to-hooking-2efb21acffd6
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/image_load/image_load_dll_dbghelp_dbgcore_unsigned_load.yml
author: Perez Diego (@darkquassar), oscd.community, Ecco, Huntrule Team
date: 2019-10-27
modified: 2022-12-09
tags:
  - attack.credential-access
  - attack.t1003.001
logsource:
  category: image_load
  product: windows
detection:
  selection:
    ImageLoaded|endswith:
      - \dbghelp.dll
      - \dbgcore.dll
    Signed: "false"
  condition: selection
falsepositives:
  - Unknown
level: high
license: DRL-1.1