[Rule Tunings] GWS Rules w/ zero alerts

[imays11]

Pull Request

Issue link(s):

• https://github.com/elastic/ia-trade-team/issues/905

Summary - What I changed

Shared tuning across four Google Workspace admin rules with zero fleet alert volume despite production maturity. All were validated in trade-lab with working queries.

Common changes:

• Scoped index to logs-google_workspace.admin-*
• Removed unnecessary event.category / event.type
• Added investigation fields
• Updated investigation guides to align with highlighted fields and current Admin console paths

Gmail routing rule — expanded scope and query (largest change):

Previously matched only legacy custom mail routes (EMAIL_ROUTE, MESSAGE_SECURITY_RULE). Now covers the full Gmail admin collection surface:

• removed filebeat index because new field is not included google_workspace.admin.setting.metadata.rule.type
• Because filebeat is removed, I reduced the lookback window to account for the much shorter poll interval + lag time the Integration uses for Admin data stream (15 min poll + 3 min lag) > from = "now-20m"
• Routing (UNIFIED_MAIL_ROUTING, legacy MESSAGE_SECURITY_RULE) — also deliver to, change envelope recipient
• Recipient address map (ALIAS_TABLE) — forwarding by address mapping
• Mail hosts / outbound gateway (EMAIL_ROUTE)
• Query matches legacy (CREATE_GMAIL_SETTING / CHANGE_GMAIL_SETTING) and current (CREATE_APPLICATION_SETTING / CHANGE_APPLICATION_SETTING) audit actions, on setting.name or setting.metadata.rule.type. These values will likely change after the migration period ending Aug 2026, we'll need to reassess this rule to make sure the values still align.

How To Test

Manually triggered each rule via the Admin console, verified they triggered as expected in our TRaDE test stack.

[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.