Windows DLL Side-Loading: OleView loading aclui.dll

Alerts on OleView.exe loading aclui.dll on Windows, excluding common benign paths to highlight potential DLL side-loading.

FreeReviewedSigma · High · v5
Product
windows
Category
image_load
Author
Swachchhanda Shrawan Poudel (SigmaHQ), DRL 1.1
Published
2024-07-31
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 Windows processes where OleView.exe loads a DLL named aclui.dll. Such DLL side-loading can be used to execute attacker-controlled code by forcing a trusted loader to load an unexpected library. The detection relies on image load telemetry indicating the loaded DLL path and the originating executable path, with exclusions for common legitimate OleView locations and signed OleView binaries.

Related detections9 linkedT1574.001 — drag to rearrange
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Windows DLL Side-Loading: OleView loading aclui.dll
Pivot detection · T1574.001 · 9 related

Changelog

v5
  1. v5
    Candidate ingested via manual entry.2026-07-31
  2. v4
    Candidate ingested via manual entry.2026-07-31
  3. v3
    Candidate ingested via manual entry.2026-07-31
  4. v2
    Candidate ingested via manual entry.2026-07-31
  5. 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.