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Windows GPO Scheduled Task Persistence via SYSVOL ScheduledTasks.xml Writes (Security 5136/5145)

Alerts on GPO changes writing ScheduledTasks.xml to SYSVOL, indicating scheduled-task persistence at scale.

FreeReviewedSigma · High · v2
Product
windows
Service
security
Author
Samir Bousseaden (SigmaHQ), DRL 1.1
Published
2019-04-03
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

Execution → Priv Esc

  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 identifies Windows Group Policy changes that add or modify scheduled task files in SYSVOL by matching specific GPO extension identifiers and write access events. Attackers abuse GPO scheduled tasks to execute payloads across many systems without installing software locally, making abuse a high-impact persistence and execution technique. It relies on Windows Security event 5136 (directory object changes for GPO extension attributes) and Security event 5145 (file share access targeting ScheduledTasks.xml under SYSVOL with write permissions).

Reporting behind it

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 GPO Scheduled Task Persistence via SYSVOL ScheduledTasks.xml Writes (Security 5136/5145)
Pivot detection · T1053.005 · 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.