huntrule

Windows DCOM InternetExplorer.Application iertutil.dll DLL Hijack Suspicion

Alerts when System writes iertutil.dll in the DCOM InternetExplorer.Application path, consistent with potential DLL hijacking.

FreeReviewedSigma · Critical · v2
Product
windows
Category
file_event
Author
Roberto Rodriguez @Cyb3rWard0g, Open Threat Research (OTR), wagga (SigmaHQ), DRL 1.1
Published
2020-10-12
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

Lateral Movement

  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

Identifies network-accessible behavior consistent with a DLL hijack attempt by watching for writes or placements of iertutil.dll under a DCOM InternetExplorer.Application path. Attackers may use DLL search order or DCOM component loading to run malicious code by replacing or planting a legitimate library. This rule relies on Windows file event telemetry showing System as the actor and TargetFilename ending with the specific iertutil.dll path segment.

Reporting behind it

Related detections9 linkedT1021.002 — drag to rearrange
Windows Security: Remote DCOM IE DLL Hijack via iertutil.dll in Internet Explorer path
Windows DCOM InternetExplorer.Application DLL Hijack via iertutil.dll Image Load
Suspicious Access to Citrix Session Evidence Registry Keys
Suspicious Ransomware Fan-Out Deployment via PsExec Spread (Qilin)
Suspicious Impacket smbexec Command Execution Pattern
Malicious Impacket Wmiexec Remote Command Execution Pattern
Suspicious Remote Admin Share Execution via Conhost
Malicious Network Share Manipulation via Commandline (via process_creation)
Suspicious Number of Oustanding SMB Requests Increased (via process_creation)
Windows DCOM InternetExplorer.Application iertutil.dll DLL Hijack Suspicion
Pivot detection · T1021.002 · 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.