Windows schtasks.exe scheduled task creation or modification with high privileges on suspicious schedule types

Flags schtasks.exe commands that create/modify tasks to run on ONLOGON/ONSTART/ONCE/ONIDLE with SYSTEM or HIGHEST privileges.

FreeReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2022-08-31
Updated
2026-07-30

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 process executions of schtasks.exe where the command line indicates the task is scheduled using ONLOGON, ONSTART, ONCE, or ONIDLE. It also requires the task run level to include high-privilege indicators such as NT AUTHORITY\SYSTEM (NT AUT), SYSTEM, or HIGHEST. Such scheduling and privilege elevation can help an attacker establish persistence or run code with elevated rights. The detection relies on Windows process creation telemetry and examines the command line for these schedule and privilege markers.

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Windows schtasks.exe scheduled task creation or modification with high privileges on suspicious schedule types
Pivot detection · T1053.005 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.