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

Alerts on unexpected loads of iviewers.dll outside Windows Kits paths, consistent with DLL sideloading attempts.

FreeReviewedSigma · High · v2
Product
windows
Category
image_load
Author
X__Junior (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2023-03-21
Updated
2026-07-31

ATT&CK techniques

Execution → Defense Evasion
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. 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.

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Windows DLL sideloading: iviewers.dll loaded from non-Windows Kits paths
Pivot detection · T1574.001 · 9 related

Changelog

v2
  1. v2
    Candidate ingested via manual entry.2026-07-31
  2. 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.