huntrule

Windows Scheduled Task Index Registry Tampering Hiding Tasks from Query Tools

Alerts on registry set events that tamper scheduled task TaskCache Tree "Index" DWORD to 0.

FreeReviewedSigma · High · v1
Product
windows
Category
registry_set
Author
Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2022-08-26
Updated
2026-07-30
AnalysisDetection

ATT&CK techniques

  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 modifications where the DWORD value named "Index" under the scheduled task TaskCache Tree registry path is set to 0x00000000. Attackers can use this to impair defenses by hiding scheduled tasks from common management and query tooling. It relies on registry set telemetry that records the TargetObject path containing the TaskCache Tree location, along with the specific value and data type.

Reporting behind it

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Windows Scheduled Task Index Registry Tampering Hiding Tasks from Query Tools
Pivot detection · T1685 · 9 related

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