Windows Task Scheduler DLL Loaded From Uncommon Directory

Flags taskschd.dll being loaded by a process from Temp/public/user directories commonly abused for malicious activity.

FreeReviewedSigma · Low · v5
Product
windows
Category
image_load
Author
Swachchhanda Shrawan Poudel (SigmaHQ), DRL 1.1
Published
2024-09-02
Updated
2026-07-31

ATT&CK techniques

Execution → Priv Esc
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Defense Evasion

  5. Cred Access

  6. Discovery

  7. Lateral Movement

  8. Collection

  9. C2

  10. Exfiltration

  11. Impact

What it detects

This rule flags when taskschd.dll is loaded and the loading image path contains one of several uncommon or potentially suspicious locations (for example Temp, Public, Downloads, Desktop). Loading this module may be associated with applications that can interact with scheduled tasks via the Windows task scheduler component. Investigation should focus on the loading process and its behavior to determine whether the DLL load is expected (e.g., during an installer) or indicative of abuse. Telemetry required includes image/DLL load events with the loaded DLL name and the image path that performed the load.

Related detections9 linkedT1053.005 — drag to rearrange
Suspicious Scheduled Task Persistence Named SchedulerLsass via schtasks (via process_creation)
Malicious SYSTEM Persistence via Scheduled Task Running rundll32 at Startup (via process_creation)
Suspicious Per-Minute SYSTEM Scheduled Task With Highest Privileges
Suspicious Scheduled Task Executing Rundll32 DLL Export by Ordinal
Suspicious Scheduled Task CacheTask Reconfigured to Run as SYSTEM
Malicious NodeSnake RAT Persistence via Scheduled Task and Node.js (via process_creation)
Malicious Scheduled Task Masquerading as Windows Defender Sync via schtasks (via process_creation)
Suspicious Scheduled Task Creation Launching mshta via schtasks (via process_creation)
Suspicious Service or Task Named windowsinspectionupdate (via process_creation)
Windows Task Scheduler DLL Loaded From Uncommon Directory
Pivot detection · T1053.005 · 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.