[Rule Tuning] A scheduled task was created

[Mikaayenson]

Resolves elastic/ia-trade-team#1004

Reduces noise from widespread benign scheduled task creation by expanding the TaskName exclusion list. Adds filters for PRTG monitoring sensors, AMD driver updates, Microsoft PowerToys autorun tasks, Windows DeviceLicensingService and MRT tasks, OneDrive per-machine updates, Lenovo OEM tasks, Barco ClickShare, Blazer Browser, Zoom VDI management, and Npcap watchdog tasks. Also widens the HP WarrantyChecker exclusion to cover machine-specific task name suffixes.

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Full telemetry triage, analytics links, and KQL verification: see linked ia-trade-team issue.

[github-actions]

Rule: Tuning - Guidelines

These guidelines serve as a reminder set of considerations when tuning an existing rule.

Documentation and Context

• Detailed description of the suggested changes.
• Provide example JSON data or screenshots.
• Provide evidence of reducing benign events mistakenly identified as threats (False Positives).
• Provide evidence of enhancing detection of true threats that were previously missed (False Negatives).
• Provide evidence of optimizing resource consumption and execution time of detection rules (Performance).
• Provide evidence of specific environment factors influencing customized rule tuning (Contextual Tuning).
• Provide evidence of improvements made by modifying sensitivity by changing alert triggering thresholds (Threshold Adjustments).
• Provide evidence of refining rules to better detect deviations from typical behavior (Behavioral Tuning).
• Provide evidence of improvements of adjusting rules based on time-based patterns (Temporal Tuning).
• Provide reasoning of adjusting priority or severity levels of alerts (Severity Tuning).
• Provide evidence of improving quality integrity of our data used by detection rules (Data Quality).
• Ensure the tuning includes necessary updates to the release documentation and versioning.

Rule Metadata Checks

• updated_date matches the date of tuning PR merged.
• min_stack_version should support the widest stack versions.
• name and description should be descriptive and not include typos.
• query should be inclusive, not overly exclusive. Review to ensure the original intent of the rule is maintained.

Testing and Validation

• Validate that the tuned rule's performance is satisfactory and does not negatively impact the stack.
• Ensure that the tuned rule has a low false positive rate.

[tradebot-elastic]

⛔️ Test failed

Results

• ❌ A scheduled task was created (eql)
  • coverage_issue: no_rta
  • stack_validation_failed: no_rta

[Copilot]

Pull request overview

Tunes the existing Windows persistence detection rule “A scheduled task was created” to reduce alert noise by expanding known-benign scheduled task name exclusions while keeping the rule’s overall detection logic intact.

Changes:

• Updated the rule metadata updated_date to 2026/07/10.
• Expanded winlog.event_data.TaskName exclusions to cover additional common benign scheduled tasks (monitoring tools, OEM updaters, Microsoft components, and other frequently observed software tasks).
• Consolidated HP WarrantyChecker exclusions by switching to a wildcard pattern to cover machine-specific suffix variants.

[w0rk3r]

Uses an attacker controlled variable. Will tune (rewrite) this one once we collect telemetry for the new scheduled task fields.