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[Rule Tuning] Windows High-Severity Rules Revamp - 13#6032

Merged
w0rk3r merged 5 commits into
mainfrom
revamp_12
May 12, 2026
Merged

[Rule Tuning] Windows High-Severity Rules Revamp - 13#6032
w0rk3r merged 5 commits into
mainfrom
revamp_12

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@w0rk3r

@w0rk3r w0rk3r commented May 3, 2026

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Issues

Part of https://github.com/elastic/ia-trade-team/issues/619
Part of https://github.com/elastic/ia-trade-team/issues/844
Part of https://github.com/elastic/ia-trade-team/issues/205
Part of https://github.com/elastic/ia-trade-team/issues/636

Summary

This PR fixes/improves our Windows rules by:

  • Improving our investigation guides to be question-driven and actionable, with clear pivots and specific information vs our old checklists
  • Adding Investigate Timeline plugins to help analysts quickly pivot into related alerts, authentication events, file activity, child processes, network activity, directory-service changes, and follow-on Windows Security events
  • Adding setup guides
  • Adding Highlighted fields
  • Fixing/Improving metadata where needed (Description, Mitre tags, references)
  • Improving the order of the fields, so the most relevant information (Name, description, query) are visible without scrolling down too much
  • Tunings where needed (Expand logic, exclude FPs, etc.)

Screenshots / Sample

Highlighted Fields:
image

Investigation Guides: Investigate Plugin

image image

Clicking the investigation plugins launches Timeline with field values populated dynamically from alert fields.

image image

@github-actions

github-actions Bot commented May 3, 2026

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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

tradebot-elastic commented May 3, 2026

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⛔️ Test failed

Results
  • ✅ Lateral Movement via Startup Folder (eql)
  • ❌ ScreenConnect Server Spawning Suspicious Processes (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Execution via TSClient Mountpoint (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Incoming DCOM Lateral Movement with MMC (eql)
    • stack_validation_failed: no_alerts - 0 alerts
  • ❌ Potential CVE-2025-33053 Exploitation (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Incoming DCOM Lateral Movement via MSHTA (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ✅ Unusual Child Process of dns.exe (eql)
  • ❌ Potential SharpRDP Behavior (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Potential Remote Desktop Shadowing Activity (eql)
    • stack_validation_failed: no_alerts - 0 alerts
  • ❌ Suspicious Kerberos Authentication Ticket Request (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta

Comment thread rules/windows/lateral_movement_credential_access_kerberos_correlation.toml Outdated
@tradebot-elastic

tradebot-elastic commented May 3, 2026

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⛔️ Test failed

Results
  • ✅ Lateral Movement via Startup Folder (eql)
  • ❌ ScreenConnect Server Spawning Suspicious Processes (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Execution via TSClient Mountpoint (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Incoming DCOM Lateral Movement with MMC (eql)
    • stack_validation_failed: no_alerts - 0 alerts
  • ❌ Potential CVE-2025-33053 Exploitation (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Incoming DCOM Lateral Movement via MSHTA (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ✅ Unusual Child Process of dns.exe (eql)
  • ❌ Potential SharpRDP Behavior (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Potential Remote Desktop Shadowing Activity (eql)
    • stack_validation_failed: no_alerts - 0 alerts
  • ❌ Suspicious Kerberos Authentication Ticket Request (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta

@botelastic botelastic Bot added the OS: macOS label May 4, 2026
This reverts commit 9af17cc.
@tradebot-elastic

tradebot-elastic commented May 4, 2026

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⛔️ Test failed

Results
  • ❌ User Added to the Admin Group (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ✅ Lateral Movement via Startup Folder (eql)
  • ❌ ScreenConnect Server Spawning Suspicious Processes (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Execution via TSClient Mountpoint (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Incoming DCOM Lateral Movement with MMC (eql)
    • stack_validation_failed: no_alerts - 0 alerts
  • ❌ Potential CVE-2025-33053 Exploitation (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Incoming DCOM Lateral Movement via MSHTA (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ✅ Unusual Child Process of dns.exe (eql)
  • ❌ Potential SharpRDP Behavior (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Potential Remote Desktop Shadowing Activity (eql)
    • stack_validation_failed: no_alerts - 0 alerts
  • ❌ Suspicious Kerberos Authentication Ticket Request (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta

@tradebot-elastic

tradebot-elastic commented May 4, 2026

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⛔️ Test failed

Results
  • ✅ Lateral Movement via Startup Folder (eql)
  • ❌ ScreenConnect Server Spawning Suspicious Processes (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Execution via TSClient Mountpoint (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Incoming DCOM Lateral Movement with MMC (eql)
    • stack_validation_failed: no_alerts - 0 alerts
  • ❌ Potential CVE-2025-33053 Exploitation (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Incoming DCOM Lateral Movement via MSHTA (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ✅ Unusual Child Process of dns.exe (eql)
  • ❌ Potential SharpRDP Behavior (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Potential Remote Desktop Shadowing Activity (eql)
    • stack_validation_failed: no_alerts - 0 alerts
  • ❌ Suspicious Kerberos Authentication Ticket Request (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta

[transform]

[[transform.investigate]]
label = "Alerts associated with the host"

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Only this one for this rule?

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As it is a 3 event sequence, there is basically nothing on the alert for us to pivot on lol

@tradebot-elastic

tradebot-elastic commented May 12, 2026

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⛔️ Test failed

Results
  • ✅ Lateral Movement via Startup Folder (eql)
  • ❌ ScreenConnect Server Spawning Suspicious Processes (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Execution via TSClient Mountpoint (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Incoming DCOM Lateral Movement with MMC (eql)
    • stack_validation_failed: no_alerts - 0 alerts
  • ❌ Potential CVE-2025-33053 Exploitation (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Incoming DCOM Lateral Movement via MSHTA (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ✅ Unusual Child Process of dns.exe (eql)
  • ❌ Potential SharpRDP Behavior (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta
  • ❌ Potential Remote Desktop Shadowing Activity (eql)
    • stack_validation_failed: no_alerts - 0 alerts
  • ❌ Suspicious Kerberos Authentication Ticket Request (eql)
    • coverage_issue: no_rta
    • stack_validation_failed: no_rta

@w0rk3r w0rk3r merged commit 6fb8fe5 into main May 12, 2026
13 checks passed
@w0rk3r w0rk3r deleted the revamp_12 branch May 12, 2026 17:44
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backport: auto Domain: Endpoint OS: macOS OS: Windows windows related rules Rule: Tuning tweaking or tuning an existing rule

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5 participants