Windows DLL sideloading: iviewers.dll loaded from non-Windows Kits paths

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1574.001DLL
Persistence
- T1574.001DLL
Priv Esc
- T1574.001DLL
Defense Evasion
- T1574.001DLL
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule flags cases where Windows loads an image ending in iviewers.dll, excluding loads from common Windows Kits directories. Loading this DLL from unexpected locations can indicate DLL sideloading, which attackers use to execute malicious code by abusing trusted loading behavior. The detection relies on image load telemetry (process/image load events) that includes the full ImageLoaded path.

Reporting behind it

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Windows DLL sideloading: iviewers.dll loaded from non-Windows Kits paths

Pivot detection · T1574.001 · 9 related

Changelog

v2

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-iviewers-dll-image-loads-4c21b805

title: "Windows DLL sideloading: iviewers.dll loaded from non-Windows Kits paths"
id: e20f1c5c-047a-4f48-81a7-0bc5b674818d
status: test
description: This rule flags cases where Windows loads an image ending in iviewers.dll, excluding loads from common Windows Kits directories. Loading this DLL from unexpected locations can indicate DLL sideloading, which attackers use to execute malicious code by abusing trusted loading behavior. The detection relies on image load telemetry (process/image load events) that includes the full ImageLoaded path.
references:
  - https://www.secureworks.com/research/shadowpad-malware-analysis
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/image_load/image_load_side_load_iviewers.yml
author: X__Junior (Nextron Systems), Huntrule Team
date: 2023-03-21
tags:
  - attack.persistence
  - attack.privilege-escalation
  - attack.execution
  - attack.stealth
  - attack.t1574.001
logsource:
  category: image_load
  product: windows
detection:
  selection:
    ImageLoaded|endswith: \iviewers.dll
  filter:
    ImageLoaded|startswith:
      - C:\Program Files (x86)\Windows Kits\
      - C:\Program Files\Windows Kits\
  condition: selection and not filter
falsepositives:
  - Unknown
level: high
license: DRL-1.1
related:
  - id: 4c21b805-4dd7-469f-b47d-7383a8fcb437
    type: derived

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